Nonautonomous matter waves in a waveguide
Yan Zhenya [Key Laboratory of Mathematics Mechanization, Institute of Systems Science, AMSS, Chinese Academy of Sciences, Beijing 100190 (China); Zhang Xiaofei [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); College of Science, Honghe University, Mengzi 661100 (China); Liu, W. M. [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2011-08-15
We present a physical model that describes the transport of Bose-Einstein-condensed atoms from a reservoir to a waveguide. By using the similarity and Moebius transformations, we study nonautonomous matter waves in Bose-Einstein condensates in the presence of an inhomogeneous source. Then, we find its various types of exact nonautonomous matter-wave solutions, including the W-shaped bright solitary waves, W-shaped and U-shaped dark solitary waves, periodic wave solutions, and rational solitary waves. The results show that these different types of matter-wave structures can be generated and effectively controlled by modulating the amplitude of the source. Our results may raise the possibility of some experiments and potential applications related to Bose-Einstein condensates in the presence of an inhomogeneous source.
Coherent matter wave optics on an atom chip
Krüger, Peter; Hofferberth, S.; Schumm, Thorsten
2006-01-01
Coherent manipulation of matter waves in microscopic trapping potentials facilitates both fundamental and technological applications. Here we focus on experiments with a microscopic integrated interferometer that demonstrate coherent operation on an atom chip.......Coherent manipulation of matter waves in microscopic trapping potentials facilitates both fundamental and technological applications. Here we focus on experiments with a microscopic integrated interferometer that demonstrate coherent operation on an atom chip....
Bigravitons as dark matter and gravitational waves
Aoki, Katsuki
2016-01-01
We consider the possibility that the massive graviton is a viable candidate of dark matter in the context of bimetric gravity. We first derive the energy-momentum tensor of the massive graviton and show that it indeed behaves as that of dark matter fluid. We then discuss a production mechanism and the present abundance of massive gravitons as dark matter. Since the metric to which ordinary matter fields couple is a linear combination of the two mass eigenstates of bigravity, production of massive gravitons, i.e. the dark matter particles, is inevitably accompanied by generation of massless gravitons, i.e. the gravitational waves. Therefore, in this scenario some information about dark matter in our universe is encoded in gravitational waves. For instance, if LIGO detects gravitational waves generated by the preheating after inflation then the massive graviton with the mass of $\\sim 0.01$ GeV is a candidate of the dark matter.
Schroedinger's Wave Structure of Matter (WSM)
Wolff, Milo; Haselhurst, Geoff
2009-10-01
The puzzling electron is due to the belief that it is a discrete particle. Einstein deduced this structure was impossible since Nature does not allow the discrete particle. Clifford (1876) rejected discrete matter and suggested structures in `space'. Schroedinger, (1937) also eliminated discrete particles writing: What we observe as material bodies and forces are nothing but shapes and variations in the structure of space. Particles are just schaumkommen (appearances). He rejected wave-particle duality. Schroedinger's concept was developed by Milo Wolff and Geoff Haselhurst (SpaceAndMotion.com) using the Scalar Wave Equation to find spherical wave solutions in a 3D quantum space. This WSM, the origin of all the Natural Laws, contains all the electron's properties including the Schroedinger Equation. The origin of Newton's Law F=ma is no longer a puzzle; It originates from Mach's principle of inertia (1883) that depends on the space medium and the WSM. Carver Mead (1999) at CalTech used the WSM to design Intel micro-chips correcting errors of Maxwell's magnetic Equations. Applications of the WSM also describe matter at molecular dimensions: alloys, catalysts, biology and medicine, molecular computers and memories. See ``Schroedinger's Universe'' - at Amazon.com
Wave Dark Matter and Dwarf Spheroidal Galaxies
Parry, Alan R.
We explore a model of dark matter called wave dark matter (also known as scalar field dark matter and boson stars) which has recently been motivated by a new geometric perspective by Bray. Wave dark matter describes dark matter as a scalar field which satisfies the Einstein-Klein-Gordon equations. These equations rely on a fundamental constant Upsilon (also known as the "mass term'' of the Klein-Gordon equation). Specifically, in this dissertation, we study spherically symmetric wave dark matter and compare these results with observations of dwarf spheroidal galaxies as a first attempt to compare the implications of the theory of wave dark matter with actual observations of dark matter. This includes finding a first estimate of the fundamental constant Upsilon. In the introductory Chapter 1, we present some preliminary background material to define and motivate the study of wave dark matter and describe some of the properties of dwarf spheroidal galaxies. In Chapter 2, we present several different ways of describing a spherically symmetric spacetime and the resulting metrics. We then focus our discussion on an especially useful form of the metric of a spherically symmetric spacetime in polar-areal coordinates and its properties. In particular, we show how the metric component functions chosen are extremely compatible with notions in Newtonian mechanics. We also show the monotonicity of the Hawking mass in these coordinates. Finally, we discuss how these coordinates and the metric can be used to solve the spherically symmetric Einstein-Klein-Gordon equations. In Chapter 3, we explore spherically symmetric solutions to the Einstein-Klein-Gordon equations, the defining equations of wave dark matter, where the scalar field is of the form f(t, r) = eiotF(r) for some constant o ∈ R and complex-valued function F(r). We show that the corresponding metric is static if and only if F( r) = h(r)eia for some constant alpha ∈ R and real-valued function h(r). We describe the
Scalar Field (Wave) Dark Matter
Matos, T
2016-01-01
Recent high-quality observations of dwarf and low surface brightness (LSB) galaxies have shown that their dark matter (DM) halos prefer flat central density profiles. On the other hand the standard cold dark matter model simulations predict a more cuspy behavior. Feedback from star formation has been widely used to reconcile simulations with observations, this might be successful in field dwarf galaxies but its success in low mass galaxies remains uncertain. One model that have received much attention is the scalar field dark matter model. Here the dark matter is a self-interacting ultra light scalar field that forms a cosmological Bose-Einstein condensate, a mass of $10^{-22}$eV/c$^2$ is consistent with flat density profiles in the centers of dwarf spheroidal galaxies, reduces the abundance of small halos, might account for the rotation curves even to large radii in spiral galaxies and has an early galaxy formation. The next generation of telescopes will provide better constraints to the model that will help...
Multimode interferometer for guided matter waves.
Andersson, Erika; Calarco, Tommaso; Folman, Ron; Andersson, Mauritz; Hessmo, Björn; Schmiedmayer, Jörg
2002-03-11
Atoms can be trapped and guided with electromagnetic fields, using nanofabricated structures. We describe the fundamental features of an interferometer for guided matter waves, built of two combined Y-shaped beam splitters. We find that such a device is expected to exhibit high contrast fringes even in a multimode regime, analogous to a white light interferometer.
Matter-Wave Optics of Diatomic Molecules
2012-10-23
Lima , Peru (2010). S. Singh and P. Meystre, "Atomic probe Wigner tomography of a nanomechanical system," contributed paper, APS DAMOP Annual Meeting...Triangle Park , NC 27709-2211 15. SUBJECT TERMS matter-wave optics, ultracold molecules, polar molecules, quantum optomechanics, quantum-degenerate
Coordinate transformations and matter waves cloaking
Mohammadi, G.R. [Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of); Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Moghaddam, A.G. [Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731 (Iran, Islamic Republic of); Mohammadkhani, R., E-mail: rmkhani@znu.ac.ir [Department of Physics, Faculty of Science, University of Zanjan, Zanjan 45371-38791 (Iran, Islamic Republic of)
2016-03-06
Transformation method provides an efficient tool to control wave propagation inside the materials. Using the coordinate transformation approach, we study invisibility cloaks with sphere, cylinder and ellipsoid structures for electronic waves propagation. The underlying physics behind this investigation is the fact that Schrödinger equation with position dependent mass tensor and potentials has a covariant form which follows the coordinate transformation. Using this technique we obtain the exact spatial form of the mass tensor and potentials for a variety of cloaks with different shapes. - Highlights: • Invisibility cloaks for matter waves with three different geometries. • Exact analytical form of the effective mass tensor and potential. • Analogy between cloaking for quantum mechanical waves with classical electromagnetic waves. • Possible experimental realization in engineered semiconducting structures.
Ghost Imaging with Matter Waves
Khakimov, Roman; Henson, Bryce; Shin, David; Hodgman, Sean; Dall, Robert; Baldwin, Kenneth; Truscott, Andrew
2016-05-01
We demonstrate, for the first time, high resolution ghost imaging of a macroscopic object using atoms. Ghost imaging is a novel technique in which the image emerges from cross-correlation of particles (usually photons)in two separate beams. One beam is detected with a single-pixel (bucket detector) after passing through the object, while the other beam does not interact with the object and is registered with high spatial resolution. Neither detector can reconstruct the image independently. In our experiment, the two beams are formed by correlated pairs of ultracold metastable helium atoms originating from thecollision of two Bose-Einstein Condensates. After s-wave scattering the atoms form a spherical shell of strongly correlated pairs with opposite momenta. We extend this technique with more than a10-foldincrease in the number of correlated pairs available for eachsingle experiment run, by using higher-order Bragg scattering in the Kapitza-Dirac regime, with multiple shells generated from different diffraction orders. Using single-atom detection, we create ghost images of a target maskwith a resolution given by the width of the cross-corrrelation function of atomic momenta. Future extensions could include ghost interference and EPR tests.
Towards a matter wave interferometer on a sounding rocket
van Zoest, Tim; Peters, Achim; Ahlers, Holger; Wicht, Andreas; Vogel, Anika; Wenzlawski, Anderas; Deutsch, Christian; Kajari, Endre; Gaaloul, Naceur; Dittus, Hansjürg; Hartwig, Jonas; Herr, Waldemar; Herrmann, Sven; Reichel, Jakob; Bongs, Kai; Koenemann, Thorben; Laemmerzahl, Claus; Lewoczko-Adamczyk, Wojtek; Schiemangk, Max; Müntinga, Hauke; Meyer, Nadine; Rasel, Ernst Maria; Walser, Reinhold; Resch, Andreas; Rode, Christina; Seidel, Stephan; Sengstock, Klaus; Singh, Yeshpal; Schleich, Wolfgang; Ertmer, Wolfgang; Rosenbusch, Peter; Wilken, Tobias; Goeklue, Ertan
Applications of coherent matter waves are high resolution interferometers for measuring inertial and gravitational forces as well as testing fundamental physics, for which they may serve as a laser like source with mesoscopic quantum features. Out of possible applications, the test of the principle of equivalence in the quantum domain is selected as a target with the highest scientific interest on timescales of a microgravity experiment at the ISS or on a free flyer (ATV, FOTON or other satellites). The QUANTUS project demonstrated the technological feasibil-ity of coherent matter waves in microgravity. As a next step, the consortium will prepare and procure a sounding rocket mission to demonstrate technologies for matter wave interferome-try based on the broad experience of former developments with experiments in the droptower. Therefore, the experiment has to withstand strong requirements concerning environmental con-ditions (Temperature, shock, environmental pressure, etc.) and needs to be designed to fit in a 600 l volume (diameter 35 cm, length 160 cm). It is considered as an important step towards the technology required for the ISS and other platforms. These experiments will give further insights on the potential of inertial sensors based on atom interferometers and the technology is for example of interest for applications in earth observation and geodesy. They could replace classical techniques relying on test masses and promise a further improvement in the accuracy of such devices.
Detecting inertial effects with airborne matter-wave interferometry
Geiger, Remi; Stern, Guillaume; Zahzam, Nassim; Cheinet, Patrick; Battelier, Baptiste; Villing, André; Moron, Frédéric; Lours, Michel; Bidel, Yannick; Bresson, Alexandre; Landragin, Arnaud; Bouyer, Philippe
2011-01-01
Inertial sensors relying on atom interferometry offer a breakthrough advance in a variety of applications, such as inertial navigation, gravimetry or ground- and space-based tests of fundamental physics. These instruments require a quiet environment to reach their performance and using them outside the laboratory remains a challenge. Here we report the first operation of an airborne matter-wave accelerometer set up aboard a 0g plane and operating during the standard gravity (1g) and microgravity (0g) phases of the flight. At 1g, the sensor can detect inertial effects more than 300 times weaker than the typical acceleration fluctuations of the aircraft. We describe the improvement of the interferometer sensitivity in 0g, which reaches 2 x 10-4 ms-2 / \\surdHz with our current setup. We finally discuss the extension of our method to airborne and spaceborne tests of the Universality of free fall with matter waves.
Detecting inertial effects with airborne matter-wave interferometry.
Geiger, R; Ménoret, V; Stern, G; Zahzam, N; Cheinet, P; Battelier, B; Villing, A; Moron, F; Lours, M; Bidel, Y; Bresson, A; Landragin, A; Bouyer, P
2011-09-20
Inertial sensors relying on atom interferometry offer a breakthrough advance in a variety of applications, such as inertial navigation, gravimetry or ground- and space-based tests of fundamental physics. These instruments require a quiet environment to reach their performance and using them outside the laboratory remains a challenge. Here we report the first operation of an airborne matter-wave accelerometer set up aboard a 0g plane and operating during the standard gravity (1g) and microgravity (0g) phases of the flight. At 1g, the sensor can detect inertial effects more than 300 times weaker than the typical acceleration fluctuations of the aircraft. We describe the improvement of the interferometer sensitivity in 0g, which reaches 2 x 10-4 ms-2 / √Hz with our current setup. We finally discuss the extension of our method to airborne and spaceborne tests of the Universality of free fall with matter waves.
Avoided-level-crossing spectroscopy with dressed matter waves.
Eckardt, André; Holthaus, Martin
2008-12-12
We devise a method for probing resonances of macroscopic matter waves in shaken optical lattices by monitoring their response to slow parameter changes, and show that such resonances can be disabled by particular choices of the driving amplitude. The theoretical analysis of this scheme reveals far-reaching analogies between dressed atoms and time periodically forced matter waves.
Evanescent light-matter Interactions in Atomic Cladding Wave Guides
Stern, Liron; Goykhman, Ilya; Levy, Uriel
2012-01-01
Alkali vapors, and in particular rubidium, are being used extensively in several important fields of research such as slow and stored light non-linear optics3 and quantum computation. Additionally, the technology of alkali vapors plays a major role in realizing myriad industrial applications including for example atomic clocks magentometers8 and optical frequency stabilization. Lately, there is a growing effort towards miniaturizing traditional centimeter-size alkali vapor cells. Owing to the significant reduction in device dimensions, light matter interactions are greatly enhanced, enabling new functionalities due to the low power threshold needed for non-linear interactions. Here, taking advantage of the mature Complimentary Metal-Oxide-Semiconductor (CMOS) compatible platform of silicon photonics, we construct an efficient and flexible platform for tailored light vapor interactions on a chip. Specifically, we demonstrate light matter interactions in an atomic cladding wave guide (ACWG), consisting of CMOS ...
Detecting dark matter waves with precision measurement tools
Derevianko, Andrei
2016-01-01
Virialized Ultra-Light Fields (VULFs) while being viable cold dark matter candidates can also solve the standard model hierarchy problem. Direct searches for VULFs due to their non-particle nature require low-energy precision measurement tools. Here we consider scalar VULF candidates. While the previous proposals have focused on detecting coherent oscillations of the measured signals at the VULF Compton frequencies at the device location, here we point out that VULFs also have a distinct spatial signature, forming dark matter waves. Thereby the discovery reach can be improved by using distributed networks of precision measurement tools. We find the expected dark-matter wave signal by deriving spatio-temporal two-point VULF correlation function. Based on the developed formalism for coherence properties of dark-matter fields, we propose several experiments for dark matter wave detection. In the most basic version, the modifications to already running experiments are minor and only require GPS-assisted time-stam...
2015-05-05
AND SUBTITLE LASER-DRIVEN ULTRA-RELATIVISTIC PLASMAS - NUCLEAR FUSION IN COULOMB SHOCK WAVES, ROUGE WAVES, AND BACKGROUND MATTER. 5a. CONTRACT...blackbody radiation on free electrons .........................9 2.vi. Proposal of ultimate test of laser nuclear fusion efficiency in clusters...domain of energies and temperatures, with applications in particular to controlled nuclear fusion . 2. Final technical report on the grant #F49620-11-1
Wave energy converter test application
Hottola, Niko
2016-01-01
This thesis was made for wave energy company Wello Oy. Given assignment was to find the suitable generator and frequency converter for a wave energy converter test application. The primary objective was to find a suitable generator for direct drive, in order to avoid the weight of the test application rising too high. In this thesis the possible machine types for test application are presented and what are their advenatages and disadvantages. In addition, the operation of the frequency co...
Shock wave compression of condensed matter a primer
Forbes, Jerry W
2012-01-01
This book introduces the core concepts of the shock wave physics of condensed matter, taking a continuum mechanics approach to examine liquids and isotropic solids. The text primarily focuses on one-dimensional uniaxial compression in order to show the key features of condensed matter’s response to shock wave loading. The first four chapters are specifically designed to quickly familiarize physical scientists and engineers with how shock waves interact with other shock waves or material boundaries, as well as to allow readers to better understand shock wave literature, use basic data analysis techniques, and design simple 1-D shock wave experiments. This is achieved by first presenting the steady one-dimensional strain conservation laws using shock wave impedance matching, which insures conservation of mass, momentum and energy. Here, the initial emphasis is on the meaning of shock wave and mass velocities in a laboratory coordinate system. An overview of basic experimental techniques for measuring pressure...
Matter-wave interferometry in a double well on an atom chip
Schumm, Thorsten; Hofferberth, S.; Andersson, L. M.
2005-01-01
Matter-wave interference experiments enable us to study matter at its most basic, quantum level and form the basis of high-precision sensors for applications such as inertial and gravitational field sensing. Success in both of these pursuits requires the development of atom-optical elements...... that can manipulate matter waves at the same time as preserving their coherence and phase. Here, we present an integrated interferometer based on a simple, coherent matter-wave beam splitter constructed on an atom chip. Through the use of radio-frequency-induced adiabatic double-well potentials, we...... demonstrate the splitting of Bose-Einstein condensates into two clouds separated by distances ranging from 3 to 80 μm, enabling access to both tunnelling and isolated regimes. Moreover, by analysing the interference patterns formed by combining two clouds of ultracold atoms originating from a single...
Path integrals, matter waves, and the double slit
Jones, Eric R.; Bach, Roger A.; Batelaan, Herman
2015-11-01
Basic explanations of the double slit diffraction phenomenon include a description of waves that emanate from two slits and interfere. The locations of the interference minima and maxima are determined by the phase difference of the waves. An optical wave, which has a wavelength λ and propagates a distance L, accumulates a phase of 2π L/λ . A matter wave, also having wavelength λ that propagates the same distance L, accumulates a phase of π L/λ , which is a factor of two different from the optical case. Nevertheless, in most situations, the phase difference, {{Δ }}\\varphi , for interfering matter waves that propagate distances that differ by {{Δ }}L, is approximately 2π {{Δ }}L/λ , which is the same value computed in the optical case. The difference between the matter and optical case hinders conceptual explanations of diffraction from two slits based on the matter-optics analogy. In the following article we provide a path integral description for matter waves with a focus on conceptual explanation. A thought experiment is provided to illustrate the validity range of the approximation {{Δ }}\\varphi ≈ 2π {{Δ }}L/λ .
Filtering of matter wave vibrational states via spatial adiabatic passage
Loiko, Yu; Corbalán, R; Birkl, G; Mompart, J; 10.1103/PhysRevA.83.033629
2011-01-01
We discuss the filtering of the vibrational states of a cold atom in an optical trap, by chaining this trap with two empty ones and controlling adiabatically the tunneling. Matter wave filtering is performed by selectively transferring the population of the highest populated vibrational state to the most distant trap while the population of the rest of the states remains in the initial trap. Analytical conditions for two-state filtering are derived and then applied to an arbitrary number of populated bound states. Realistic numerical simulations close to state-of-the-art experimental arrangements are performed by modeling the triple well with time dependent P\\"oschl-Teller potentials. In addition to filtering of vibrational states, we discuss applications for quantum tomography of the initial population distribution and engineering of atomic Fock states that, eventually, could be used for tunneling assisted evaporative cooling.
Multiple scattering induced negative refraction of matter waves
Pinsker, Florian
2016-01-01
Starting from fundamental multiple scattering theory it is shown that negative refraction indices are feasible for matter waves passing a well-defined ensemble of scatterers. A simple approach to this topic is presented and explicit examples for systems of scatterers in 1D and 3D are stated that imply negative refraction for a generic incoming quantum wave packet. Essential features of the effective scattering field, densities and frequency spectrum of scatterers are considered. Additionally it is shown that negative refraction indices allow perfect transmission of the wave passing the ensemble of scatterers. Finally the concept of the superlens is discussed, since it is based on negative refraction and can be extended to matter waves utilizing the observations presented in this paper which thus paves the way to ‘untouchable’ quantum systems in analogy to cloaking devices for electromagnetic waves. PMID:26857266
Experimental methods of molecular matter-wave optics.
Juffmann, Thomas; Ulbricht, Hendrik; Arndt, Markus
2013-08-01
We describe the state of the art in preparing, manipulating and detecting coherent molecular matter. We focus on experimental methods for handling the quantum motion of compound systems from diatomic molecules to clusters or biomolecules.Molecular quantum optics offers many challenges and innovative prospects: already the combination of two atoms into one molecule takes several well-established methods from atomic physics, such as for instance laser cooling, to their limits. The enormous internal complexity that arises when hundreds or thousands of atoms are bound in a single organic molecule, cluster or nanocrystal provides a richness that can only be tackled by combining methods from atomic physics, chemistry, cluster physics, nanotechnology and the life sciences.We review various molecular beam sources and their suitability for matter-wave experiments. We discuss numerous molecular detection schemes and give an overview over diffraction and interference experiments that have already been performed with molecules or clusters.Applications of de Broglie studies with composite systems range from fundamental tests of physics up to quantum-enhanced metrology in physical chemistry, biophysics and the surface sciences.Nanoparticle quantum optics is a growing field, which will intrigue researchers still for many years to come. This review can, therefore, only be a snapshot of a very dynamical process.
Photofragmentation Beam Splitters for Matter-Wave Interferometry
Dörre, Nadine; Rodewald, Jonas; Geyer, Philipp; von Issendorff, Bernd; Haslinger, Philipp; Arndt, Markus
2014-12-01
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here, we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin. We propose that photofragmentation gratings can act on a large set of van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization.
Photofragmentation beam splitters for matter-wave interferometry
Dörre, Nadine; Geyer, Philipp; von Issendorff, Bernd; Haslinger, Philipp; Arndt, Markus
2014-01-01
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter-waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. Photofragmentation gratings can act on objects as different as van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin.
Coordinate transformations and matter waves cloaking
Mohammadi, G. R.; Moghaddam, A. G.; Mohammadkhani, R.
2016-03-01
Transformation method provides an efficient tool to control wave propagation inside the materials. Using the coordinate transformation approach, we study invisibility cloaks with sphere, cylinder and ellipsoid structures for electronic waves propagation. The underlying physics behind this investigation is the fact that Schrödinger equation with position dependent mass tensor and potentials has a covariant form which follows the coordinate transformation. Using this technique we obtain the exact spatial form of the mass tensor and potentials for a variety of cloaks with different shapes.
Excitation of knotted vortex lines in matter waves
Maucher, F.; Gardiner, S. A.; Hughes, I. G.
2016-06-01
We study the creation of knotted ultracold matter waves in Bose-Einstein condensates via coherent two-photon Raman transitions with a Λ level configuration. The Raman transition allows an indirect transfer of atoms from the internal state | a> to the target state | b> via an excited state | e> , that would be otherwise dipole-forbidden. This setup enables us to imprint three-dimensional knotted vortex lines embedded in the probe field to the density in the target state. We elaborate on experimental feasibility as well as on subsequent dynamics of the matter wave.
Matter-wave bright solitons in effective bichromatic lattice potentials
Golam Ali Sekh
2013-08-01
Matter-wave bright solitons in bichromatic lattice potentials are considered and their dynamics for different lattice environments are studied. Bichromatic potentials are created from superpositions of (i) two linear optical lattices and (ii) a linear and a nonlinear optical lattice. Effective potentials are found for the solitons in both bichromatic lattices and a comparative study is done on the dynamics of solitons with respect to the effective potentials. The effects of dispersion on solitons in bichromatic lattices are studied and it is found that the dispersive spreading can be minimized by appropriate combinations of lattice and interaction parameters. Stability of nondispersive matter-wave solitons is checked from phase portrait analysis.
Quantum interference of molecules -- probing the wave nature of matter
Venugopalan, Anu
2012-01-01
The double slit interference experiment has been famously described by Richard Feynman as containing the "only mystery of quantum mechanics". The history of quantum mechanics is intimately linked with the discovery of the dual nature of matter and radiation. While the double slit experiment for light is easily undertsood in terms of its wave nature, the very same experiment for particles like the electron is somewhat more difficult to comprehend. By the 1920s it was firmly established that electrons have a wave nature. However, for a very long time, most discussions pertaining to interference experiments for particles were merely gedanken experiments. It took almost six decades after the establishment of its wave nature to carry out a 'double slit interference' experiment for electrons. This set the stage for interference experiments with larger particles. In the last decade there has been spectacular progress in matter-wave interefernce experiments. Today, molecules with over a hundred atoms can be made to i...
Wave packet dynamics of the matter wave field of a Bose-Einstein condensate
Sudheesh, C; Lakshmibala, S
2004-01-01
We show in the framework of a tractable model that revivals and fractional revivals of wave packets afford clear signatures of the extent of departure from coherence and from Poisson statistics of the matter wave field in a Bose-Einstein condensate, or of a suitably chosen initial state of the radiation field propagating in a Kerr-like medium.
Weak Nonlinear Matter Waves in a Trapped Spin-1 Condensates
CAI Hong-Qiang; YANG Shu-Rong; XUE Ju-Kui
2011-01-01
The dynamics of the weak nonlinear matter solitary waves in a spin-1 condensates with harmonic external potential are investigated analytically by a perturbation method. It is shown that, in the small amplitude limit, the dynamics of the solitary waves are governed by a variable-coefficient Korteweg-de Vries (KdV) equation. The reduction to the (KdV) equation may be useful to understand the dynamics of nonlinear matter waves in spinor BEGs. The analytical expressions for the evolution of soliton show that the small-amplitude vector solitons of the mixed types perform harmonic oscillations in the presence of the trap. Furthermore, the emitted radiation profiles and the soliton oscillation freauencv are also obtained.
Modal decomposition of a propagating matter wave via electron ptychography
Cao, S.; Kok, P.; Li, P.; Maiden, A. M.; Rodenburg, J. M.
2016-12-01
We employ ptychography, a phase-retrieval imaging technique, to show experimentally that a partially coherent high-energy matter (electron) wave emanating from an extended source can be decomposed into a set of mutually independent modes of minimal rank. Partial coherence significantly determines the optical transfer properties of an electron microscope and so there has been much work on this subject. However, previous studies have employed forms of interferometry to determine spatial coherence between discrete points in the wave field. Here we use the density matrix to derive a formal quantum mechanical description of electron ptychography and use it to measure a full description of the spatial coherence of a propagating matter wave field, at least within the fundamental uncertainties of the measurements we can obtain.
Matter-wave diffraction at the natural limit
Brand, Christian; Sclafani, Michele; Knobloch, Christian; Lilach, Yigal; Juffmann, Thomas; Kotakoski, Jani; Mangler, Clemens; Winter, Andreas; Turchanin, Andrey; Meyer, Jannik; Cheshnovsky, Ori; Arndt, Markus
2016-05-01
The high sensitivity of matter-wave interferometry experiments to forces and perturbations makes them an essential tool for precision measurements and tests of quantum physics. While mostly grating made of laser-light are used, material gratings have the advantage that they are independent of the particle's internal properties. This makes them universally applicable. However, the molecules will experience substantial van der Waals shifts while passing the grating slits, which suggests limiting this perturbation by reducing the material thickness. In a comprehensive study we compared the van der Waals interactions for free-standing gratings made from single and double layer graphene to masks commonly used in atom interferometry. From the population of high fringe orders we deduce a surprisingly strong electrical interaction between the polarizable molecules and the nanomasks. As even for these thinnest diffraction elements which-path information is not shared with the environment, we interpret this as an experimental affirmation of Bohr's arguments in his famous debate with Einstein.
Black Hole Window into p-Wave Dark Matter Annihilation.
Shelton, Jessie; Shapiro, Stuart L; Fields, Brian D
2015-12-01
We present a new method to measure or constrain p-wave-suppressed cross sections for dark matter (DM) annihilations inside the steep density spikes induced by supermassive black holes. We demonstrate that the high DM densities, together with the increased velocity dispersion, within such spikes combine to make thermal p-wave annihilation cross sections potentially visible in γ-ray observations of the Galactic center (GC). The resulting DM signal is a bright central point source with emission originating from DM annihilations in the absence of a detectable spatially extended signal from the halo. We define two simple reference theories of DM with a thermal p-wave annihilation cross section and establish new limits on the combined particle and astrophysical parameter space of these models, demonstrating that Fermi Large Area Telescope is currently sensitive to thermal p-wave DM over a wide range of possible scenarios for the DM distribution in the GC.
Hybridizing matter-wave and classical accelerometers
Lautier, J.; Volodimer, L.; Hardin, T.; Merlet, S.; Lours, M.; Pereira Dos Santos, F.; Landragin, A.
2014-10-01
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.
Hybridizing matter-wave and classical accelerometers
Lautier, J.; Volodimer, L.; Hardin, T.; Merlet, S.; Lours, M.; Pereira Dos Santos, F.; Landragin, A., E-mail: arnaud.landragin@obspm.fr [LNE-SYRTE, Observatoire de Paris, CNRS, UPMC, 61 avenue de l' Observatoire, 75014 Paris (France)
2014-10-06
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.
Hybridizing matter-wave and classical accelerometers
Lautier, Jean; Hardin, Thomas; Merlet, Sebastien; Santos, Franck Pereira Dos; Landragin, Arnaud
2014-01-01
We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performances without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely the dead times between consecutive measurements.
Selective Sommerfeld Enhancement of p-wave Dark Matter Annihilation
Das, Anirban
2016-01-01
We point out a mechanism for selective Sommerfeld enhancement (suppression) of odd (even) partial waves of dark matter co/annihilation. Using this, the usually velocity-suppressed p-wave annihilation can dominate the annihilation signals in the present Universe. The selection mechanism is a manifestation of an exchange symmetry, and generic for DM with off-diagonal long-range interactions. As a consequence, the relic and late-time annihilation rates are parametrically different and a distinctive phenomenology, with large but strongly velocity-dependent annihilation rates, is predicted.
Influence of conformational molecular dynamics on matter wave interferometry
Gring, Michael; Eibenberger, Sandra; Nimmrichter, Stefan; Berrada, Tarik; Arndt, Markus; Ulbricht, Hendrik; Hornberger, Klaus; Müri, Marcel; Mayor, Marcel; Böckmann, Marcus; Doltsinis, Nikos
2014-01-01
We investigate the influence of thermally activated internal molecular dynamics on the phase shifts of matter waves inside a molecule interferometer. While de Broglie physics generally describes only the center-of-mass motion of a quantum object, our experiment demonstrates that the translational quantum phase is sensitive to dynamic conformational state changes inside the diffracted molecules. The structural flexibility of tailor-made hot organic particles is sufficient to admit a mixture of strongly fluctuating dipole moments. These modify the electric susceptibility and through this the quantum interference pattern in the presence of an external electric field. Detailed molecular dynamics simulations combined with density functional theory allow us to quantify the time-dependent structural reconfigurations and to predict the ensemble-averaged square of the dipole moment which is found to be in good agreement with the interferometric result. The experiment thus opens a new perspective on matter wave interfe...
Decoherence of matter waves by thermal emission of radiation
Hackermüller, L; Brezger, B; Zeilinger, Anton; Arndt, M; Hackermueller, Lucia; Hornberger, Klaus; Brezger, Bjoern; Zeilinger, Anton; Arndt, Markus
2004-01-01
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find...
Gravitational Waves From SU(N) Glueball Dark Matter
Soni, Amarjit
2016-01-01
A hidden sector with pure non-abelian gauge symmetry is an elegant and just about the simplest model of dark matter. In this model the dark matter candidate is the lightest bound state made of the confined gauge fields, the dark glueball. In spite of its simplicity, the model has been shown to have several interesting non-standard implications in cosmology. In this work, we explore the gravitational waves from binary boson stars made of self-gravitating dark glueball fields as a natural and important consequence. We derive the dark SU($N$) star mass and radius as functions of the only two fundamental parameters in the model, the glueball mass $m$ and the number of colors $N$, and identify the regions that could be probed by the LIGO and future gravitational wave observatories.
Decoherence of matter waves by thermal emission of radiation
2004-01-01
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external ph...
Wave functions in SUSY cosmological models with matter
Ortiz, C. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico); Rosales, J.J. [Facultad de Ingenieria Mecanica Electrica y Electronica, Universidad de Guanajuato, Prolongacion Tampico 912, Bellavista, Salamanca, Guanajuato (Mexico); Socorro, J. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico)]. E-mail: socorro@fisica.ugto.mx; Torres, J. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico); Tkach, V.I. [Instituto de Fisica de la Universidad de Guanajuato, A.P. E-143, C.P. 37150, Leon, Guanajuato (Mexico)
2005-06-06
In this work we consider the n=2 supersymmetric superfield approach for the FRW cosmological model and the corresponding term of matter content, perfect fluid with barotropic state equation p={gamma}{rho}. We are able to obtain a normalizable wave function (at zero energy) of the universe. Besides, the mass parameter spectrum is found for the closed FRW case in the Schrodinger picture, being similar to those obtained by other methods, using a black hole system.
New avenues for matter-wave-enhanced spectroscopy
Rodewald, Jonas; Haslinger, Philipp; Dörre, Nadine; Stickler, Benjamin A.; Shayeghi, Armin; Hornberger, Klaus; Arndt, Markus
2017-01-01
We present matter-wave interferometry as a tool to advance spectroscopy for a wide class of nanoparticles, clusters and molecules. The high sensitivity of de Broglie interference fringes to external perturbations enables measurements in the limit of an individual particle absorbing only a single photon on average, or even no photon at all. The method allows one to extract structural and electronic information from the loss of the interference contrast. It is minimally invasive and works even for dilute ensembles.
Peptides and proteins in matter wave interferometry: Challenges and prospects
Sezer, Ugur; Geyer, Philipp; Mairhofer, Lukas; Brand, Christian; Doerre, Nadine; Rodewald, Jonas; Schaetti, Jonas; Koehler, Valentin; Mayor, Marcel; Arndt, Markus
2016-05-01
Recent developments in matter wave physics suggest that quantum interferometry with biologically relevant nanomaterials is becoming feasible for amino acids, peptides, proteins and RNA/DNA strands. Quantum interference of biomolecules is interesting as it can mimic Schrödinger's cat states with molecules of high mass, elevated temperature and biological functionality. Additionally, the high internal complexity can give rise to a rich variety of couplings to the environment and new handles for quantitative tests of quantum decoherence. Finally, matter wave interferometers are highly sensitive force sensors and pave the way for quantum-assisted measurements of biomolecular properties in interaction with tailored or biomimetic environments. Recent interferometer concepts such as the Kapitza-Dirac-Talbot-Lau interferometer (KDTLI) or the Optical Time-domain Matter Wave interferometer (OTIMA) have already proven their potential for quantum optics in the mass range beyond 10000 amu and for metrology. Here we show our advances in quantum interferometry with vitamins and peptides and discuss methods of realizing cold, intense and sufficiently slow beams of synthetically tailored or hydrated polypeptides with promising properties for a new generation of quantum optics.
Transverse multipolar light-matter couplings in evanescent waves
Fernandez-Corbaton, Ivan; Bonod, Nicolas; Rockstuhl, Carsten
2016-01-01
We present an approach to study the interaction between matter and evanescent fields. The approach is based on the decomposition of evanescent plane waves into multipoles of well-defined angular momentum transverse to both decay and propagation directions. We use the approach to identify the origin of the recently observed directional coupling of emitters into guided modes, and of the opposite Zeeman state excitation of atoms near a fiber. We explain how to rigorously quantify both effects, and show that the directionality and the difference in excitation rates grow exponentially with the multipolar order of the light-matter interaction. We also use the approach to study and maximize the transverse torque exerted by an evanescent plane wave onto a given spherical absorbing particle. The maximum occurs at the quadrupolar order of the particle, and for a particular polarization of the plane wave. All the obtained physical insights can be traced back to the two main features of the decomposition of evanescent pl...
Discrete Wave-Packet Representation in Nuclear Matter Calculations
Müther, H; Kukulin, V I; Pomerantsev, V N
2016-01-01
The Lippmann-Schwinger equation for the nucleon-nucleon $t$-matrix as well as the corresponding Bethe-Goldstone equation to determine the Brueckner reaction matrix in nuclear matter are reformulated in terms of the resolvents for the total two-nucleon Hamiltonians defined in free space and in medium correspondingly. This allows to find solutions at many energies simultaneously by using the respective Hamiltonian matrix diagonalization in the stationary wave packet basis. Among other important advantages, this approach simplifies greatly the whole computation procedures both for coupled-channel $t$-matrix and the Brueckner reaction matrix. Therefore this principally novel scheme is expected to be especially useful for self-consistent nuclear matter calculations because it allows to accelerate in a high degree single-particle potential iterations. Furthermore the method provides direct access to the properties of possible two-nucleon bound states in the nuclear medium. The comparison between reaction matrices f...
Into the lair: gravitational-wave signatures of dark matter
Macedo, Caio F B; Cardoso, Vitor; Crispino, Luis C B
2013-01-01
The nature and properties of dark matter (DM) are both outstanding issues in physics. The universal character of gravity implies that self-gravitating compact DM configurations are not only possible, but likely to be spread throughout the universe. The astrophysical signature of these objects may be used to probe fundamental particle physics, or even to provide an alternative description of compact objects in active galactic nuclei. Here we discuss the most promising dissection tool of these configurations: the inspiral of a compact stellar-size object and consequent gravitational-wave emission. The inward motion of this "test probe" encodes unique information about the nature of the central, supermassive DM configuration. When the probe travels through some compact DM profile we show that, within a Newtonian approximation, the quasi-adiabatic evolution of the inspiral is mainly driven by DM accretion into the small compact object and by dynamical friction, rather than by gravitational-wave radiation-reaction...
Matter-wave beam splitter on an atom chip for a portable atom interferometer
Kim, S. J.; Yu, H.; Gang, S. T.; Kim, J. B.
2017-05-01
We constructed a matter-wave beam splitter on an atom chip using a 87Rb Bose-Einstein condensate. Using radio-frequency-induced double-well potentials, we were able to coherently split a BEC into two clouds separated by distances ranging from 2.8 to 57 μm. Interference between these two freely expanding BECs was observed, confirming the coherence of the matter-wave beam splitter. We are able to control the distance and the angle between the split BECs by varying the rf-field's amplitude, frequency, or polarization. From the perspective of practical use, our BEC manipulation system is suitable for application to interferometry. It is compact, and by anodic bonding the atom chip to the vacuum cell, the repetition rate is kept high. The portable system occupies a volume of 0.5 m3 and operates at a repetition rate as high as 0.2 Hz using a commercial vacuum product.
Decoherence of matter waves by thermal emission of radiation.
Hackermüller, Lucia; Hornberger, Klaus; Brezger, Björn; Zeilinger, Anton; Arndt, Markus
2004-02-19
Emergent quantum technologies have led to increasing interest in decoherence--the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find good quantitative agreement between our experimental observations and microscopic decoherence theory. Decoherence by emission of thermal radiation is a general mechanism that should be relevant to all macroscopic bodies.
Coherent transport of matter waves in disordered optical potentials
Kuhn, Robert
2007-07-01
The development of modern techniques for the cooling and the manipulation of atoms in recent years, and the possibility to create Bose-Einstein condensates and degenerate Fermi gases and to load them into regular optical lattices or disordered optical potentials, has evoked new interest for the disorder-induced localization of ultra-cold atoms. This work studies the transport properties of matter waves in disordered optical potentials, which are also known as speckle potentials. The effect of correlated disorder on localization is first studied numerically in the framework of the Anderson model. The relevant transport parameters in the configuration average over many different realizations of the speckle potential are then determined analytically, using self-consistent diagrammatic perturbation techniques. This allows to make predictions for a possible experimental observation of coherent transport phenomena for cold atoms in speckle potentials. Of particular importance are the spatial correlations of the speckle fluctuations, which are responsible for the anisotropic character of the single scattering processes in the effective medium. Coherent multiple scattering leads to quantum interference effects, which entail a renormalization of the diffusion constant as compared to the classical description. This so-called weak localization of matter waves is studied as the underlying mechanism for the disorder-driven transition to the Anderson-localization regime, explicitly taking into account the correlations of the speckle fluctuations. (orig.)
Leilei Jia
2014-01-01
Full Text Available By using the bifurcation theory of dynamical systems, we present the exact representation and topological classification of coherent matter waves in Bose-Einstein condensates (BECs, such as solitary waves and modulate amplitude waves (MAWs. The existence and multiplicity of such waves are determined by the parameter regions selected. The results show that the characteristic of coherent matter waves can be determined by the “angular momentum” in attractive BECs while for repulsive BECs; the waves of the coherent form are all MAWs. All exact explicit parametric representations of the above waves are exhibited and numerical simulations support the result.
Discrete wave-packet representation in nuclear matter calculations
Müther, H.; Rubtsova, O. A.; Kukulin, V. I.; Pomerantsev, V. N.
2016-08-01
The Lippmann-Schwinger equation for the nucleon-nucleon t matrix as well as the corresponding Bethe-Goldstone equation to determine the Brueckner reaction matrix in nuclear matter are reformulated in terms of the resolvents for the total two-nucleon Hamiltonians defined in free space and in medium correspondingly. This allows one to find solutions at many energies simultaneously by using the respective Hamiltonian matrix diagonalization in the stationary wave-packet basis. Among other important advantages, this approach simplifies greatly the whole computation procedures both for the coupled-channel t matrix and the Brueckner reaction matrix. Therefore this principally novel scheme is expected to be especially useful for self-consistent nuclear matter calculations because it allows one to accelerate in a high degree single-particle potential iterations. Furthermore the method provides direct access to the properties of possible two-nucleon bound states in the nuclear medium. The comparison between reaction matrices found via the numerical solution of the Bethe-Goldstone integral equation and the straightforward Hamiltonian diagonalization shows a high accuracy of the method suggested. The proposed fully discrete approach opens a new way to an accurate treatment of two- and three-particle correlations in nuclear matter on the basis of the three-particle Bethe-Faddeev equation by an effective Hamiltonian diagonalization procedure.
Jeans Analysis for Dwarf Spheroidal Galaxies in Wave Dark Matter
Chen, Shu-Rong; Chiueh, Tzihong
2016-01-01
Observations suggest that dwarf spheroidal (dSph) galaxies exhibit large constant-density cores in the centers, which can hardly be explained by dissipationless cold dark matter simulations. Wave dark matter (${\\psi {\\rm DM}}$), characterized by a single parameter, the dark matter particle mass $m_{\\psi}$, predicts a central soliton core in every galaxy arising from quantum pressure against gravity. Here we apply Jeans analysis to the kinematic data of eight classical dSphs so as to constrain $m_{\\psi}$, and obtain $m_{\\psi}=1.18_{-0.24}^{+0.28}\\times10^{-22}{\\,\\rm eV}$ and $m_{\\psi}=1.79_{-0.33}^{+0.35}\\times10^{-22}{\\,\\rm eV}~(2\\sigma)$ using the observational data sets of Walker et al. (2007) and Walker et al. (2009b), respectively. We show that the estimate of $m_{\\psi}$ is sensitive to the dSphs kinematic data sets and is robust to various models of stellar density profile. We also consider multiple stellar subpopulations in dSphs and find consistent results. This mass range of $m_{\\psi}$ is in good agre...
Water Waves The Mathematical Theory with Applications
Stoker, J J
2011-01-01
Offers an integrated account of the mathematical hypothesis of wave motion in liquids with a free surface, subjected to gravitational and other forces. Uses both potential and linear wave equation theories, together with applications such as the Laplace and Fourier transform methods, conformal mapping and complex variable techniques in general or integral equations, methods employing a Green's function. Coverage includes fundamental hydrodynamics, waves on sloping beaches, problems involving waves in shallow water, the motion of ships and much more.
Fortov, Vladimir E.
2007-04-01
The physical properties of hot dense matter over a broad domain of the phase diagram are of immediate interest in astrophysics, planetary physics, power engineering, controlled thermonuclear fusion, impulse technologies, enginery, and several special applications. The use of intense shock waves in dynamic physics and high-pressure chemistry has made the exotic high-energy-density states of matter a subject of laboratory experiments and enabled advancing by many orders of magnitude along the pressure scale to range into the megabars and even gigabars. The present report reviews the latest experimental research involving shock waves in nonideal plasmas under conditions of strong collective interparticle interaction. The results of investigations into the thermodynamic, transport, and optical properties of strongly compressed hot matter, as well as into its composition and conductivity, are discussed. Experimental techniques for high energy density cumulation, the drivers of intense shock waves, and methods for the fast diagnostics of high-energy plasma are considered. Also discussed are compression-stimulated physical effects: pressure-induced ionization, plasma phase transitions, the deformation of bound states, plasma blooming ('transparentization' of plasma), etc. Suggestions for future research are put forward.
Index of refraction of molecular nitrogen for sodium matter waves
Loreau, J; Dalgarno, A
2013-01-01
We calculate the index of refraction of sodium matter waves propagating through a gas of nitrogen molecules. We use a recent ab initio potential for the ground state of the NaN_2 Van der Waals complex to perform quantal close-coupling calculations and compute the index of refraction as a function of the projectile velocity. We obtain good agreement with the available experimental data. We show that the refractive index contains glory oscillations, but that they are damped by the averaging over the thermal motion of the N_2 molecules. These oscillations appear at lower temperatures and projectile velocity. We also investigate the behavior of the refractive index at low temperature and low projectile velocity to show its dependence on the rotational state of N_2, and discuss the advantage of using diatomic molecules as projectiles.
Matter, dark matter and gravitational waves from a GUT-scale U(1) phase transition
Domcke, Valerie
2013-09-15
The cosmological realization of the spontaneous breaking of B-L, the difference of baryon and lepton number, can generate the initial conditions for the hot early universe. In particular, we show that entropy, dark matter and a matter-antimatter asymmetry can be produced in accordance with current observations. If B-L is broken at the grand unification scale, F-term hybrid inflation can be realized in the false vacuum of unbroken B-L. The phase transition at the end of inflation, governed by tachyonic preheating, spontaneously breaks the U(1){sub B-L} symmetry and sets the initial conditions for the following perturbative reheating phase. We provide a detailed, time-resolved picture of the reheating process. The competition of cosmic expansion and entropy production leads to an intermediate plateau of constant temperature, which controls both the generated lepton asymmetry and the dark matter abundance. This enables us to establish relations between the neutrino and superparticle mass spectrum, rendering this mechanism testable. Moreover, we calculate the entire gravitational wave spectrum for this setup. This yields a promising possibility to probe cosmological B - L breaking with forthcoming gravitational wave detectors such as eLISA, advanced LIGO and BBO/DECIGO. The largest contribution is obtained from cosmic strings which is, for typical parameter values, at least eight orders of magnitude higher then the contribution from inflation. Finally, we study the possibility of realizing hybrid inflation in a superconformal framework. We find that superconformal D-term inflation is an interesting possibility generically leading to a two-field inflation model, but in its simplest version disfavoured by the recently published Planck data.
Spin waves theory and applications
Stancil, Daniel D
2009-01-01
Magnetic materials can support propagating waves of magnetization; since these are oscillations in the magneto static properties of the material, they are called magneto static waves (sometimes 'magnons' or 'magnetic polarons'). This book discusses magnetic properties of materials, and magnetic moments of atoms and ions
Millimeter-wave antennas configurations and applications
du Preez, Jaco
2016-01-01
This book comprehensively reviews the state of the art in millimeter-wave antennas, traces important recent developments and provides information on a wide range of antenna configurations and applications. While fundamental theoretical aspects are discussed whenever necessary, the book primarily focuses on design principles and concepts, manufacture, measurement techniques, and practical results. Each of the various antenna types scalable to millimeter-wave dimensions is considered individually, with coverage of leaky-wave and surface-wave antennas, printed antennas, integrated antennas, and reflector and lens systems. The final two chapters address the subject from a systems perspective, providing an overview of supporting circuitry and examining in detail diverse millimeter-wave applications, including high-speed wireless communications, radio astronomy, and radar. The vast amount of information now available on millimeter-wave systems can be daunting for researchers and designers entering the field. This b...
Fundamentals and Applications of Ultrasonic Waves
Cheeke, J David N
2012-01-01
Designed specifically for newcomers to the field, this fully updated second edition begins with fundamentals and quickly advances beyond general wave concepts into an in-depth treatment of ultrasonic waves in isotropic media. Focusing on the physics of acoustic waves, their propagation, technology, and applications, this accessible overview of ultrasonics includes accounts of viscoelasticity and multiple scattering. It examines new technologies, including atomic force acoustic microscopy, lasers, micro-acoustics, and nanotechnology. In addition, it highlights both direct and indirect applicati
Integrable multi atom matter-radiation models without rotating wave approximation
Kundu, Anjan
2004-01-01
Interacting matter-radiation models close to physical systems are proposed, which without rotating wave approximation and with matter-matter interactions are Bethe ansatz solvable. This integrable system is constructed from the elliptic Gaudin model at high spin limit, where radiative excitation can be included perturbatively.
Sound Wave in Hot Dense Matter Created in Heavy Ion Collision
Sun, X.; Yang, Z.
2005-01-01
A model to study the sound wave in hot dense matter created in heavy ion collisions by jet is proposed.The preliminary data of jet shape analysis of PHENIX Collaboration for all centralities and two directions is well explained in this model. Then the wavelength of the sound wave, the natural frequency of the hot dense matter and the speed of sound wave are estimated from the fit.
The Sagnac effect: 20 years of development in matter-wave interferometry
Barrett, Brynle; Dutta, Indranil; Meunier, Matthieu; Canuel, Benjamin; Gauguet, Alexandre; Bouyer, Philippe; Landragin, Arnaud
2014-01-01
Since the first atom interferometry experiments in 1991, measurements of rotation through the Sagnac effect in open-area atom interferometers has been studied. These studies have demonstrated very high sensitivity which can compete with state-of-the-art optical Sagnac interferometers. Since the early 2000s, these developments have been motivated by possible applications in inertial guidance and geophysics. Most matter-wave interferometers that have been investigated since then are based on two-photon Raman transitions for the manipulation of atomic wave packets. Results from the two most studied configurations, a space-domain interferometer with atomic beams and a time-domain interferometer with cold atoms, are presented and compared. Finally, the latest generation of cold atom interferometers and their preliminary results are presented.
Medical and biomedical applications of shock waves
Loske, Achim M
2017-01-01
This book provides current, comprehensive, and clear explanations of the physics behind medical and biomedical applications of shock waves. Extracorporeal shock wave lithotripsy is one of the greatest medical advances of our time, and its techniques and clinical devices are continuously evolving. Further research continues to improve the understanding of calculi fragmentation and tissue-damaging mechanisms. Shock waves are also used in orthopedics and traumatology. Possible applications in oncology, cardiology, dentistry, gene therapy, cell transfection, transformation of fungi and bacteria, as well as the inactivation of microorganisms are promising approaches for clinical treatment, industrial applications and research. Medical and Biomedical Applications of Shock Waves is useful as a guide for students, technicians and researchers working in universities and laboratories. Chemists, biologists, physicians and veterinarians, involved in research or clinical practice will find useful advice, but also engineer...
Dual Matter-Wave Inertial Sensors in Weightlessness
Barrett, Brynle; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe
2016-01-01
Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the best precision achievable on Earth is limited by the free-fall time of the atoms, and their full potential can only be realized in Space where interrogation times of many seconds will lead to unprecedented sensitivity. Various mission scenarios are presently being pursued which plan to implement matter-wave inertial sensors. Toward this goal, we realize the first onboard operation of simultaneous $^{87}$Rb $-$ $^{39}$K interferometers in the weightless environment produced during parabolic flight. The large vibration levels ($10^{-2}~g/\\sqrt{\\rm Hz}$), acceleration range ($0-1.8~g$) and rotation rates ($5$ deg/s) during flight present significant challenges. We demonstrate the capability of our dual-quantum sensor by measuring the E\\"{o}tv\\"{o}s parameter with systematic-limited uncertainties of $1.1 \\times 10^{-3}$ and $3.0 \\times 10^{-4}$ during standard- a...
Les Houches Summer School of Theoretical Physics : Session 72, Coherent Atomic Matter Waves
Westbrook, C; David, F; Coherent Atomic Matter Waves
2001-01-01
Progress in atomic physics has been so vigorous during the past decade that one is hard pressed to follow all the new developments. In the early 1990s the first atom interferometers opened a new field in which we have been able to use the wave nature of atoms to probe fundamental quantum me chanics questions as well as to make precision measurements. Coming fast on the heels of this development was the demonstration of Bose Einstein condensation in dilute atomic vapors which intensified research interest in studying the wave nature of matter, especially in a domain in which "macro scopic" quantum effects (vortices, stimulated scattering of atomic beams) are visible. At the same time there has been much progress in our understanding of the behavior of waves (notably electromagnetic) in complex media, both periodic and disordered. An obvious topic of speculation and probably of future research is whether any new insight or applications will develop if one examines the behavior of de Broglie waves in ana...
Search for light scalar dark matter with atomic gravitational wave detectors
Arvanitaki, Asimina; Hogan, Jason M; Rajendran, Surjeet; Van Tilburg, Ken
2016-01-01
We show that gravitational wave detectors based on a type of atom interferometry are sensitive to ultralight scalar dark matter. Such dark matter can cause temporal oscillations in fundamental constants with a frequency set by the dark matter mass, and amplitude determined by the local dark matter density. The result is a modulation of atomic transition energies. This signal is ideally suited to a type of gravitational wave detector that compares two spatially separated atom interferometers referenced by a common laser. Such a detector can improve on current searches for electron-mass or electric-charge modulus dark matter by up to 10 orders of magnitude in coupling, in a frequency band complementary to that of other proposals. It demonstrates that this class of atomic sensors is qualitatively different from other gravitational wave detectors, including those based on laser interferometry. By using atomic-clock-like interferometers, laser noise is mitigated with only a single baseline. These atomic sensors ca...
On Wave Dark Matter, Shells in Elliptical Galaxies, and the Axioms of General Relativity
Bray, Hubert L
2012-01-01
This paper is a sequel to the author's paper entitled "On Dark Matter, Spiral Galaxies, and the Axioms of General Relativity" [arXiv:1004.4016] which explored a geometrically natural axiomatic definition for dark matter modeled by a scalar field satisfying the Einstein-Klein-Gordon wave equations which, after much calculation, was shown to be consistent with the observed spiral and barred spiral patterns in disk galaxies. We give an update on where things stand on this "wave dark matter" model of dark matter (aka scalar field dark matter and boson stars), an interesting alternative to the WIMP model of dark matter, and discuss how it has the potential to help explain the long-observed interleaved shell patterns, also known as ripples, in the images of elliptical galaxies.
Self-induced dipole force and filamentation instability of a matter wave
Saffman, M.
1998-01-01
The interaction of copropagating electromagnetic and matter waves is described with a set of coupled higher-order nonlinear Schrodinger equations. Optical self-focusing modulates an initially planar wave leading to the generation of dipole forces on the atoms. Atomic channeling due to the dipole...
Coherent control of light-matter interactions in polarization standing waves
Fang, Xu; MacDonald, Kevin F.; Plum, Eric; Zheludev, Nikolay I.
2016-08-01
We experimentally demonstrate that standing waves formed by two coherent counter-propagating light waves can take a variety of forms, offering new approaches to the interrogation and control of polarization-sensitive light-matter interactions in ultrathin (subwavelength thickness) media. In contrast to familiar energy standing waves, polarization standing waves have constant electric and magnetic energy densities and a periodically varying polarization state along the wave axis. counterintuitively, anisotropic ultrathin (meta)materials can be made sensitive or insensitive to such polarization variations by adjusting their azimuthal angle.
Bouyer, P.
2015-12-01
Since its first demonstration in 1991, Atomic Interferometry (AI) has shown to be an extremely performing probe of inertial forces. More recently, AI has revealed sensitivities to acceleration or rotation competing with or even beating state-of-the art sensors based on other technologies. The high stability and accuracy of AI sensors relying on cold atoms is at the basis of several applications ranging from fundamental physics (e.g. tests of general relativity and measurements of fundamental constants), geophysics (gravimetry, gradiometry) and inertial navigation. We are currently building a large scale matter-wave detector which will open new applications in geoscience and fundamental physics. In contrast to standard AI based sensors, our matter-wave laser interferometer gravitation antenna (MIGA) exploits the superb seismic environment of a low noise underground laboratory. This new infrastructure is embedded into the LSBB underground laboratory, in France, ideally located away from major anthropogenic disturbances and benefitting from very low background noise. MIGA combines atom and laser interferometry techniques, manipulating an array of atomic ensembles distributed along the antenna to simultanously read out seismic effects, inertial effects and eventually the passage of a gravity wave. The first version uses a set of three atomic sensors placed along an optical cavity. The spatial resolution obtained with this configuration will enable the separation of the seismic, inertial and GW contributions. This technique will bring unprecedented sensitivities to gravity gradients variations and open new perspectives for sub Hertz gravity wave and geodesic detection. MIGA will provide measurements of gravity gradients variations limited only by the AI shot noise, which will allow sensitivities of about 10-13 s-2Hz-1/2@ 2Hz. This instrument will then be capable to spatially resolve 1 m3 of water a distances of about 100 m, which opens important potential applications
Development of a portable matter-wave gravimeter
Desruelle, B.; Menoret, V.; Bouyer, P.; Landragin, A.
2013-12-01
This paper presents the results of the research activities conducted by our company for the development of its Absolute Quantum Gravimeter. This instrument relies on the utilization of a free-falling cloud of cold rubidium atoms, whose vertical acceleration is characterized using advanced matter-wave interferometry techniques. In order to meet the tight requirements expressed by geophysicists for field utilization, we have implemented several technological innovations, which allow us to combine state-of-the-art performance with simple operation and excellent transportability. The architecture of our gravimeter is based on the following innovations: - a hollow pyramidal reflector allows us to achieve all the functions (trapping, cooling, atomic state selection, interferometry and detection) with a single laser beam [1]. This scheme leads to a drastic simplification of the sensor head, and a strong reduction of its mass and volume. - An all-fibered laser system based on the frequency doubling of a seed laser operating at 1560 nm [2]. With this approach, we are able to obtain a very compact, reliable and easy to use laser source capable of generating two optical frequencies in the 780.23 nm range with an output power in excess of 250 mW, an excellent polarization extinction ratio and a fast tunability. - a real-time system dedicated to the compensation of ground vibrations [3]. This technique is based on the operation of a low noise seismometer, whose AC acceleration signal is used to correct the atomic interferometer signal. We give a detailed presentation of the instrument architecture and summarize the experimental results we have obtained with our first generation prototype. [1] A cold atom pyramidal gravimeter with a single laser beam, Q. Bodart et al, Appl. Phys. Lett. 96, 134101 (2010) [2] "Light-pulse atom interferometry in microgravity", G. Stern et al, Eur. Phys. J. D 53, 353-357 (2009) [3]. "Limits in the sensitivity of a compact atomic interferometer ", J
Gravity, holography and applications to condensed matter
Baggioli, Matteo
2016-01-01
Momentum relaxation is an ever-present and unavoidable ingredient of any realistic condensed matter system. In real-world materials the presence of a lattice, impurities or disorder forces momentum to dissipate and leads to relevant physical effects such as the finiteness of the DC transport properties, i.e. conductivities. The main purpose of this thesis is the introduction of momentum dissipation and its consequent effects into the framework of AdS/CMT, namely the applications of the gauge-gravity duality to condensed matter. A convenient and effective way of breaking the translational symmetry associated to such a conservation law is provided by massive gravity (MG) bulk theories. We consider generic massive gravity models embedded into asymptotically Anti de Sitter spacetime and we analyze them using holographic techniques. We study in detail their consistency and stability. We then focus our attention on the transport properties of the CFT duals. A big part of our work is devoted to the analysis of the e...
Some Applications of Surface Acoustic Wave Sensors
2000-01-01
The paper describes the evaluation of thin amorphous magnetic film by using of surface acoustic waves on piezo electric substrate. The obtained experimental data show strong dependence of material parameters on the annealing temperature. The mixed ferromagnetic/SAW devices for electronic applications will be also discussed.
Observation of atomic speckle and Hanbury Brown-Twiss correlations in guided matter waves.
Dall, R G; Hodgman, S S; Manning, A G; Johnsson, M T; Baldwin, K G H; Truscott, A G
2011-01-01
Speckle patterns produced by multiple independent light sources are a manifestation of the coherence of the light field. Second-order correlations exhibited in phenomena such as photon bunching, termed the Hanbury Brown-Twiss effect, are a measure of quantum coherence. Here we observe for the first time atomic speckle produced by atoms transmitted through an optical waveguide, and link this to second-order correlations of the atomic arrival times. We show that multimode matter-wave guiding, which is directly analogous to multimode light guiding in optical fibres, produces a speckled transverse intensity pattern and atom bunching, whereas single-mode guiding of atoms that are output-coupled from a Bose-Einstein condensate yields a smooth intensity profile and a second-order correlation value of unity. Both first- and second-order coherence are important for applications requiring a fully coherent atomic source, such as squeezed-atom interferometry.
Matter-wave beam splitter on an atom chip for a portable atom-interferometer
Kim, S J; Gang, S T; Kim, J B
2016-01-01
We construct a matter-wave beam splitter using 87Rb Bose-Einstein condensate on an atom chip. Through the use of radio-frequency-induced double-well potentials, we were able to split a BEC into two clouds separated by distances ranging from 2.8 {\\mu}m to 57 {\\mu}m. Interference between these two freely expanding BECs has been observed. By varying the rf-field amplitude, frequency, or polarization, we investigate behaviors of the beam-splitter. From the perspective of practical use, our BEC manipulation system is suitable for application to interferometry since it is compact and the repetition rate is high due to the anodic bonded atom chip on the vacuum cell. The portable system occupies a volume of 0.5 m3 and operates at a repetition rate as high as ~0.2 Hz.
A smartphone application for earthquakes that matter!
Bossu, Rémy; Etivant, Caroline; Roussel, Fréderic; Mazet-Roux, Gilles; Steed, Robert
2014-05-01
Smartphone applications have swiftly become one of the most popular tools for rapid reception of earthquake information for the public, some of them having been downloaded more than 1 million times! The advantages are obvious: wherever someone's own location is, they can be automatically informed when an earthquake has struck. Just by setting a magnitude threshold and an area of interest, there is no longer the need to browse the internet as the information reaches you automatically and instantaneously! One question remains: are the provided earthquake notifications always relevant for the public? What are the earthquakes that really matters to laypeople? One clue may be derived from some newspaper reports that show that a while after damaging earthquakes many eyewitnesses scrap the application they installed just after the mainshock. Why? Because either the magnitude threshold is set too high and many felt earthquakes are missed, or it is set too low and the majority of the notifications are related to unfelt earthquakes thereby only increasing anxiety among the population at each new update. Felt and damaging earthquakes are the ones that matter the most for the public (and authorities). They are the ones of societal importance even when of small magnitude. A smartphone application developed by EMSC (Euro-Med Seismological Centre) with the financial support of the Fondation MAIF aims at providing suitable notifications for earthquakes by collating different information threads covering tsunamigenic, potentially damaging and felt earthquakes. Tsunamigenic earthquakes are considered here to be those ones that are the subject of alert or information messages from the PTWC (Pacific Tsunami Warning Centre). While potentially damaging earthquakes are identified through an automated system called EQIA (Earthquake Qualitative Impact Assessment) developed and operated at EMSC. This rapidly assesses earthquake impact by comparing the population exposed to each expected
Workshop on Waves and Particles in Light and Matter
Van der Merwe, Alwyn; Waves and Particles in Light and Matter
1994-01-01
The Great Veil, Reality, and Louis de Broglie (O. Costa de Beauregard). The Fallacy of the Arguments Against Local Realism in Quantum Phenomena (A.O. Barut). Restoring Locality with FasterThanLight Velocities (P.H. Eberhard). The WaveParticle Duality and the AharonovBohm Effect (M. Ferrero, E. Santos). De Broglie's Waves in Space and Time (A. Garuccio). Interferometry with De Broglie Waves (F. Hasselbach). Quantum Mechanics of Ultracold Neutrons (V.K. Ignatovich). The Physical Interpretation of Special Relativity (S.J. Prokhovnik). Quantum Neutron Optics (H. Rauch). Some Comments on th
Do Neutrino Wave Functions Overlap and Does it Matter?
Li, Cheng-Hsien
2016-01-01
Studies of neutrinos commonly ignore anti-symmetrization of their wave functions. This implicitly assumes that either spatial wave functions for neutrinos with approximately the same momentum do not overlap or their overlapping has no measurable consequences. We examine these assumptions by considering the evolution of three-dimensional neutrino wave packets (WPs). We find that it is perfectly adequate to treat accelerator and reactor neutrinos as separate WPs for typical experimental setup. While solar and supernova neutrinos correspond to overlapping WPs, they can be treated effectively as non-overlapping for analyses of their detection.
Rain waves-wind waves interaction application to scatterometry
Kharif, C.; Giovanangeli, J. P.; Bliven, L.
1989-01-01
Modulation of a rain wave pattern by longer waves has been studied. An analytical model taking into account capillarity effects and obliquity of short waves has been developed. Modulation rates in wave number and amplitude have been computed. Experiments were carried out in a wave tank. First results agree with theoretical models, but higher values of modulation rates are measured. These results could be taken into account for understanding the radar response from the sea surface during rain.
Near Shore Wave Modeling and applications to wave energy estimation
Zodiatis, G.; Galanis, G.; Hayes, D.; Nikolaidis, A.; Kalogeri, C.; Adam, A.; Kallos, G.; Georgiou, G.
2012-04-01
The estimation of the wave energy potential at the European coastline is receiving increased attention the last years as a result of the adaptation of novel policies in the energy market, the concernsfor global warming and the nuclear energy security problems. Within this framework, numerical wave modeling systems keep a primary role in the accurate description of wave climate and microclimate that is a prerequisite for any wave energy assessment study. In the present work two of the most popular wave models are used for the estimation of the wave parameters at the coastline of Cyprus: The latest parallel version of the wave model WAM (ECMWF version), which employs new parameterization of shallow water effects, and the SWAN model, classically used for near shore wave simulations. The results obtained from the wave models near shores are studied by an energy estimation point of view: The wave parameters that mainly affect the energy temporal and spatial distribution, that is the significant wave height and the mean wave period, are statistically analyzed,focusing onpossible different aspects captured by the two models. Moreover, the wave spectrum distribution prevailing in different areas are discussed contributing, in this way, to the wave energy assessmentin the area. This work is a part of two European projects focusing on the estimation of the wave energy distribution around Europe: The MARINA platform (http://www.marina-platform.info/ index.aspx) and the Ewave (http://www.oceanography.ucy.ac.cy/ewave/) projects.
Fundamentals and applications of ultrasonic waves
Cheeke, J David N
2002-01-01
Ultrasonics. A subject with applications across all the basic sciences, engineering, medicine, and oceanography, yet even the broader topic of acoustics is now rarely offered at undergraduate levels. Ultrasonics is addressed primarily at the doctoral level, and texts appropriate for beginning graduate students or newcomers to the field are virtually nonexistent.Fundamentals and Applications of Ultrasonic Waves fills that void. Designed specifically for senior undergraduates, beginning graduate students, and those just entering the field, it begins with the fundamentals, but goes well beyond th
Compact dark matter objects, asteroseismology, and gravitational waves radiated by sun
Pokrovsky, Yu. E., E-mail: Pokrovskiy-YE@nrcki.ru [National Research Center Kurchatov Institute (Russian Federation)
2015-12-15
The solar surface oscillations observed by Crimean Astrophysical Observatory and Solar Helioseismic Observatory are considered to be excited by a small fraction of Dark Matter in form of Compact Dark Matter Objects (CDMO) in the solar structure. Gravitational Waves (GW) radiated by these CDMO are predicted to be the strongest at the Earth and are easily detectable by European Laser Interferometer Space Antenna or by Gravitational-Wave Observatory “Dulkyn” which can solve two the most challenging tasks in the modern physics: direct detection of GW and DM.
Long-living BLOCH oscillations of matter waves in periodic potentials.
Salerno, M; Konotop, V V; Bludov, Yu V
2008-07-18
The dynamics of matter waves in linear and nonlinear optical lattices subject to a spatially uniform linear force is studied both analytically and numerically. It is shown that by properly designing the spatial dependence of the scattering length it is possible to induce long-living Bloch oscillations of gap-soliton matter waves in optical lattices. This occurs when the effective nonlinearity and the effective mass of the soliton have opposite signs for all values of the crystal momentum in the Brillouin zone. The results apply to all systems modeled by the periodic nonlinear Schrödinger equation, including propagation of light in photonic and photorefractive crystals with tilted band structures.
Compact dark matter objects, asteroseismology, and gravitational waves radiated by sun
Pokrovsky, Yu. E.
2015-12-01
The solar surface oscillations observed by Crimean Astrophysical Observatory and Solar Helioseismic Observatory are considered to be excited by a small fraction of Dark Matter in form of Compact Dark Matter Objects (CDMO) in the solar structure. Gravitational Waves (GW) radiated by these CDMO are predicted to be the strongest at the Earth and are easily detectable by European Laser Interferometer Space Antenna or by Gravitational-Wave Observatory "Dulkyn" which can solve two the most challenging tasks in the modern physics: direct detection of GW and DM.
On gravitational wave-Cherenkov radiation from photons when passing through diffused dark matters
Yi, Shu-Xu
2017-03-01
Analogous to Cherenkov radiation, when a particle moves faster than the propagation velocity of gravitational wave in matter (v > cg), we expect gravitational wave-Cherenkov radiation (GWCR). In the situation that a photon travels across diffuse dark matters, the GWCR condition is always satisfied, photon will thence lose its energy all along the path. This effect has long been ignored in the practice of astrophysics and cosmology without justification with serious calculation. We study this effect for the first time, and shows that this energy loss time of the photon is far longer than the Hubble time and therefore justify the practice of ignoring this effect in the context of astrophysics.
Concept of an ionizing time-domain matter-wave interferometer
Nimmrichter, Stefan; Haslinger, Philipp; Hornberger, Klaus; ARNDT, Markus
2011-01-01
We discuss the concept of an all-optical and ionizing matter-wave interferometer in the time domain. The proposed setup aims at testing the wave nature of highly massive clusters and molecules, and it will enable new precision experiments with a broad class of atoms, using the same laser system. The propagating particles are illuminated by three pulses of a standing ultraviolet laser beam, which detaches an electron via efficient single photon-absorption. Optical gratings may have periods as ...
Measuring the Gouy Phase of Matter Waves using Singular Atom Optics with Spinor BECs
Schultz, Justin T.; Hansen, Azure; Murphree, Joseph D.; Jayaseelan, Maitreyi; Bigelow, Nicholas P.
2016-05-01
The Gouy phase is a propagation-dependent geometric phase found in confined waves as they propagate through a focus. Although it has been observed and studied extensively both in scalar and vector optical beams as well as in electron vortex beams, it has not yet been directly observed in ultracold matter waves. The Schrödinger equation has the same form as the paraxial wave equation from electromagnetism; expansion of a BEC upon release from a trap has the same mathematical form as a beam propagating away from a focus. We employ and extend this analogy between coherent optical beams and coherent matter waves to include spin angular momentum (polarization), which enables us measure the matter wave Gouy phase using coreless vortex spin textures in spinor BECs. Because the Gouy phase is dependent on the orbital angular momentum of the wave, the vortex and core states acquire different Gouy phase shifts. Parameters that are sensitive to the relative phase such as two-dimensional maps of the Stokes parameters rotate during evolution due to this phase difference. Using atom-optic polarimetry we can access the evolution of the atomic Stokes parameters and observe this rotation.
Shock Wave Attenuation Using Foam Obstacles: Does Geometry Matter?
Hongjoo Jeon
2015-06-01
Full Text Available A shock wave impact study on open and closed cell foam obstacles was completed to assess attenuation effects with respect to different front face geometries of the foam obstacles. Five different types of geometries were investigated, while keeping the mass of the foam obstacle constant. The front face, i.e., the side where the incident shock wave impacts, were cut in geometries with one, two, three or four convergent shapes, and the results were compared to a foam block with a flat front face. Results were obtained by pressure sensors located upstream and downstream of the foam obstacle, in addition to high-speed schlieren photography. Results from the experiments show no significant difference between the five geometries, nor the two types of foam.
The role of Mie scattering in the seeding of matter-wave superradiance
Bachelard, Romain; Courteille, Philippe W; Piovella, Nicola; Stehle, Christian; Zimmermann, Claus; Slama, Sebastian
2012-01-01
Matter-wave superradiance is based on the interplay between ultracold atoms coherently organized in momentum space and a backscattered wave. Here, we show that this mechanism may be triggered by Mie scattering from the atomic cloud. We show that the system evolves into a superposition of states, where the scattering process imprints a {\\it phase grating} on the atomic dipoles. This grating generates coherent emission even when there is at most one excited atom in the system at a time, contributing to the backward light wave onset. The atomic recoil 'halos' created by the scattered light exhibit a strong anisotropy, in contrast to single-atom scattering.
Kampel, Nir Shlomo; Griesmaier, Axel Rudolf; Steenstrup, Mads Peter Hornbak;
2012-01-01
We investigate experimentally the effects of light assisted collisions on the coherence between momentum states in Bose-Einstein condensates. The onset of superradiant Rayleigh scattering serves as a sensitive monitor for matter-wave coherence. A subtle interplay of binary and collective effects...
Parametric amplification of matter waves in dipolar spinor Bose-Einstein condensates
Deuretzbacher, F.; Gebreyesus, G.; Topic, O.;
2010-01-01
Spin-changing collisions may lead under proper conditions to the parametric amplification of matter waves in spinor Bose-Einstein condensates. Magnetic dipole-dipole interactions, although typically very weak in alkali-metal atoms, are shown to play a very relevant role in the amplification process...
P-wave holographic superconductor/insulator phase transitions affected by dark matter sector
Rogatko, Marek
2015-01-01
The holographic approach to building the p-wave superconductors results in three different models: the Maxwell-vector, the SU(2) Yang-Mills and the helical one. In the probe limit approximation, we analytically examine the properties of the first two models in the theory with {\\it dark matter} sector. It turns out that the effect of dark matter on the Maxwell-vector p-wave model is the same as on the s-wave superconductor studied earlier. For the non-Abelian model we study the phase transitions between p-wave holographic insulator/superconductor and metal/superconductor. Studies of marginally stable modes in the theory under consideration allow us to determine features of p-wave holographic droplet in a constant magnetic field. The superconducting transition temperature increases with the growth of the {\\it dark matter} sector coupling constant $\\alpha$, while the critical chemical potential $\\mu_c$ for the quantum phase transition between insulator and metal is a decreasing function of $\\alpha$.
Electroweak interaction of particles with accelerated matter and astrophysical applications
Dvornikov, Maxim
2015-01-01
The description of physical processes in accelerated frames opens a window to numerous new phenomena. One can encounter these effects both in the subatomic world and on a macroscale. In the present work we review our recent results on the study of the electroweak interaction of particles with an accelerated background matter. In our analysis we choose the noninertial comoving frame, where matter is at rest. Our study is based on the solution of the Dirac equation, which exactly takes into account both the interaction with matter and the nonintertial effects. First, we study the interaction of ultrarelativistic neutrinos, electrons and quarks with the rotating matter. We consider the influence of the matter rotation on the resonance in neutrino oscillations and the generation of anomalous electric current of charged particles along the rotation axis. Then, we study the creation of neutrino-antineutrino pairs in a linearly accelerated matter. The applications of the obtained results for elementary particle phys...
Detecting the gravitational wave background from primordial black hole dark matter
Clesse, Sebastien
2016-01-01
The black hole merging rates inferred after the gravitational-wave detection by Advanced LIGO/VIRGO and the relatively high mass of the progenitors are consistent with models of dark matter made of massive primordial black holes (PBH). PBH binaries emit gravitational waves in a broad range of frequencies that will be probed by future space interferometers (LISA) and pulsar timing arrays (PTA). The amplitude of the stochastic gravitational-wave background expected for PBH dark matter is calculated taking into account various effects such as initial eccentricity of binaries, PBH velocities, mass distribution and clustering. It allows a detection by the LISA space interferometer, and possibly by the PTA of the SKA radio-telescope. Interestingly, one can distinguish this background from the one of non-primordial massive binaries through a specific frequency dependence, resulting from the maximal impact parameter of binaries formed by PBH capture, depending on the PBH velocity distribution and their clustering pro...
Matter-wave dark solitons in box-like traps
Sciacca, M; Parker, N G
2016-01-01
Motivated by the experimental development of quasi-homogeneous Bose-Einstein condensates confined in box-like traps, we study numerically the dynamics of dark solitons in such traps at zero temperature. We consider the cases where the side walls of the box potential rise either as a power-law or a Gaussian. While the soliton propagates through the homogeneous interior of the box without dissipation, it typically dissipates energy during a reflection from a wall through the emission of sound waves, causing a slight increase in the soliton's speed. We characterise this energy loss as a function of the wall parameters. Moreover, over multiple oscillations and reflections in the box-like trap, the energy loss and speed increase of the soliton can be significant, although the decay eventually becomes stabilized when the soliton equilibrates with the ambient sound field.
Semi-classical description of matter wave interferometers and hybrid quantum systems
Schneider, Mathias
2015-02-16
This work considers the semi-classical description of two applications involving cold atoms. This is, on one hand, the behavior of a BOSE-EINSTEIN condensate in hybrid systems, i.e. in contact with a microscopic object (carbon nanotubes, fullerenes, etc.). On the other, the evolution of phase space distributions in matter wave interferometers utilizing ray tracing methods was discussed. For describing condensates in hybrid systems, one can map the GROSS-PITAEVSKII equation, a differential equation in the complex-valued macroscopic wave function, onto a system of two differential equations in density and phase. Neglecting quantum dispersion, one obtains a semiclassical description which is easily modified to incorporate interactions between condensate and microscopical object. In our model, these interactions comprise attractive forces (CASIMIR-POLDER forces) and loss of condensed atoms due to inelastic collisions at the surface of the object. Our model exhibited the excitation of sound waves that are triggered by the object's rapid immersion, and spread across the condensate thereafter. Moreover, local particle loss leads to a shrinking of the bulk condensate. We showed that the total number of condensed particles is decreasing potentially in the beginning (large condensate, strong mean field interaction), while it decays exponentially in the long-time limit (small condensate, mean field inetraction negligible). For representing the physics of matter wave interferometers in phase space, we utilized the WIGNER function. In semi-classical approximation, which again consists in ignoring the quantum dispersion, this representation is subject to the same equation of motion as classical phase space distributions, i.e. the LIOUVILLE equation. This implies that time evolution of theWIGNER function follows a phase space flow that consists of classical trajectories (classical transport). This means, for calculating a time-evolved distribution, one has know the initial
Phased annular array transducers for ultrasonic guided wave applications
Yan, Fei; Borigo, Cody; Liang, Yue; Koduru, Jaya P.; Rose, Joseph L.
2011-04-01
Mode and frequency control always plays an important role in ultrasonic guided wave applications. In this paper, theoretical understanding of guided wave excitations of axisymmetric sources on plate structures is established. It is shown that a wave number spectrum can be used to investigate the guided wave excitations of an axisymmetric source. The wave number spectrum is calculated from a Hankel transform of the axial source loading profile. On the basis of the theoretical understanding, phased annular array transducers are developed as a powerful tool for guided wave mode and frequency control. By applying appropriate time delays to phase the multiple elements of an annular array transducer, guided wave mode and frequency tuning can be achieved fully electronically. The phased annular array transducers have been successfully used for various applications. Example applications presented in this paper include phased annular arrays for guided wave beamforming and a novel ultrasonic vibration modal analysis technique for damage detection.
Gravitational waves from dark matter collapse in a star
Kurita, Yasunari
2016-01-01
We investigate the collapse of clusters of weakly interacting massive particles (WIMPs) in the core of a Sun-like star and the possible formation of mini-black holes and the emission of gravity waves. When the number of WIMPs is small, thermal pressure balances the WIMP cluster's self gravity. If the number of WIMPs is larger than a critical number, thermal pressure cannot balance gravity and the cluster contracts. If WIMPs are collisionless and bosonic, the cluster collapses directly to form a mini-black hole. For fermionic WIMPs, the cluster contracts until it is sustained by Fermi pressure, forming a small compact object. If the fermionic WIMP mass is smaller than $4\\times 10^2$ GeV, the radius of the compact object is larger than its Schwarzschild radius and Fermi pressure temporally sustains its self gravity, halting the formation of a black hole. If the fermionic WIMP mass is larger than $4\\times 10^2$ GeV, the radius is smaller than its Schwarzschild radius and the compact object becomes a mini-black h...
Accuracy of Satellite-Measured Wave Heights in the Australian Region for Wave Power Applications
Meath, Sian E.; Aye, Lu; Haritos, Nicholas
2008-01-01
This article focuses on the accuracy of satellite data, which may then be used in wave power applications. The satellite data are compared to data from wave buoys, which are currently considered to be the most accurate of the devices available for measuring wave characteristics. This article presents an analysis of satellite- (Topex/Poseidon) and…
Non-isentropic layers in matter behind shock and ramp compression waves
Khishchenko, Konstantin V
2014-01-01
According to the ideal fluid dynamics approach, the temperature and entropy values of a medium undergo a jump increase in the shock front as well as on contact interface between different materials after the shock wave propagation, but remain constant behind the shock front out of the contact interface. In the real condensed matter, the shock fronts and transition regions near the interfaces have finite thicknesses; therefore, the temperature field is disturbed around the interfaces. In this work, such disturbances are numerically analyzed for the problems of formation of the steady shock wave at impact and ramp loading of metals, reflection of the steady shock wave from a free surface, and the shock wave passing through the interface between two different materials. Theoretical analysis and computations show that the non-isentropic layers (the high-entropy ones with the increased temperature and the low-entropy ones with the decreased temperature) arise near the interfaces in the above problems of shock and ...
Applicability of WaveWatch-III wave model to fatigue assessment of offshore floating structures
Zou, Tao; Kaminski, Miroslaw Lech
2016-09-01
In design and operation of floating offshore structures, one has to avoid fatigue failures caused by action of ocean waves. The aim of this paper is to investigate the applicability of WaveWatch-III wave model to fatigue assessment of offshore floating structures. The applicability was investigated for Bluewaters' FPSO (Floating Production, Storage and Offloading) which had been turret moored at Sable field for half a decade. The waves were predicted as sea-state time series consisting of one wind sea and one swell. The predicted waves were compared with wave data obtained from ERA-interim and buoy measurements. Furthermore, the fatigue calculations were also carried out for main deck and side shell locations. It has been concluded that predicted fatigue damages of main deck using WaveWatch-III are in a very good agreement regardless of differences in predicted wind waves and swells caused by differences in wave system partitioning. When compared to buoy measurements, the model underestimates fatigue damages of side shell by approximately 30 %. The reason for that has been found in wider directional spreading of actual waves. The WaveWatch-III wave model has been found suitable for the fatigue assessment. However, more attention should be paid on relative wave directionality, wave system partitioning and uncertainty analysis in further development.
The Einstein-Klein-Gordon Equations, Wave Dark Matter, and the Tully-Fisher Relation
Goetz, Andrew S
2015-01-01
We examine the Einstein equation coupled to the Klein-Gordon equation for a complex-valued scalar field. These two equations together are known as the Einstein-Klein-Gordon system. In the low-field, non-relativistic limit, the Einstein-Klein-Gordon system reduces to the Poisson-Schr\\"odinger system. We describe the simplest solutions of these systems in spherical symmetry, the spherically symmetric static states, and some scaling properties they obey. We also describe some approximate analytic solutions for these states. The EKG system underlies a theory of wave dark matter, also known as scalar field dark matter (SFDM), boson star dark matter, and Bose-Einstein condensate (BEC) dark matter. We discuss a possible connection between the theory of wave dark matter and the baryonic Tully-Fisher relation, which is a scaling relation observed to hold for disk galaxies in the universe across many decades in mass. We show how fixing boundary conditions at the edge of the spherically symmetric static states implies T...
Gravitational Wave Signatures of Dark Matter Sub-Millimeter Primordial Black Holes
Davoudiasl, Hooman
2016-01-01
We entertain the possibility that primordial black holes of mass $\\sim (10^{24} - 10^{26})$ g, with sub-millimeter Schwarzschild radii, constitute all or a significant fraction of cosmic dark matter, as allowed by various constraints. In case such primordial black holes get captured in orbits around neutron stars or astrophysical black holes in our galactic neighborhood, gravitational waves from the resulting "David & Goliath" binaries could be detectable at Advanced LIGO or Advanced Virgo from days to years, for a range of possible parameters. The proposed Einstein Telescope would further expand the reach for dark matter primordial black holes in this search mode.
Evolutions of matter-wave bright soliton with spatially modulated nonlinearity
Yongshan Cheng; Fei Liu
2009-01-01
The evolution characteristics of a matter-wave bright soliton are investigated by means of the variational approach in the presence of spatially varying nonlinearity.It is found that the atom density envelope of the soliton is changed as a result of the spatial variation of the s-wave scattering length.The stable soliton can exist in appropriate initial conditions.The movement of the soliton depends on the sign and value of the coefficient of spatially modulated nonlinearity.These theoretical predictions are confirmed by the full numerical simulations of the one-dimensional Gross-Pitaevskii equation.
Cox, Kevin C; Wu, Baochen; Thompson, James K
2016-01-01
We demonstrate a method to generate spatially homogeneous entangled, spin-squeezed states of atoms appropriate for maintaining a large amount of squeezing even after release into the arm of a matter-wave interferometer or other free space quantum sensor. Using an effective intracavity dipole trap, we allow atoms to move along the cavity axis and time average their coupling to the standing wave used to generate entanglement via collective measurements, demonstrating 11(1) dB of directly observed spin squeezing. Our results show that time averaging in collective measurements can greatly reduce the impact of spatially inhomogeneous coupling to the measurement apparatus.
Zero-order filter for diffractive focusing of de Broglie matter waves
Eder, S. D.; Ravn, A. K.; Samelin, B.
2017-01-01
conditions the atom focusing at lower source stagnation pressures (broader velocity distributions) is better than what has previously been predicted. We present simulations with the software ray-tracing simulation package MCSTAS using a realistic helium source configuration, which gives very good agreement......The manipulation of neutral atoms and molecules via their de Broglie wave properties, also referred to asde Broglie matter wave optics, is relevant for several fields ranging from fundamental quantum mechanics testsand quantum metrology to measurements of interaction potentials and new imaging...
Constraining the MIT Bag Model of Quark Matter with Gravitational Wave Observations
Benhar, O; Gualtieri, L; Marassi, S; Benhar, Omar; Ferrari, Valeria; Gualtieri, Leonardo; Marassi, Stefania
2006-01-01
Most theoretical studies of strange stars are based on the MIT bag model of quark matter, whose main parameter, the bag constant B, is only loosely constrained by phenomenology. We discuss the possibility that detection of gravitational waves emitted by a compact star may provide information on both the nature of the source and the value of B. Our results show that the combined knowledge of the frequency of the emitted gravitational wave and of the mass or the radiation radius of the source allows one to discriminate between strange stars and neutron stars and set stringent bounds on the bag constants.
Localization of Matter Fields in the 5D Standing Wave Braneworld
Gogberashvili, Merab
2012-01-01
We investigate the localization problem of matter fields within the 5D standing wave braneworld. In this model the brane emits anisotropic waves into the bulk with different amplitudes along different spatial dimensions. We show that in the case of increasing warp factor there exist the pure gravitational localization of all kinds of quantum and classical particles on the brane. For classical particles the anisotropy of the background metric is hidden, brane fields exhibit standard Lorentz symmetry in spite of anisotropic nature of the primordial 5D metric.
Canuel B.
2014-01-01
Full Text Available We are building a hybrid detector of new concept that couples laser and matter-wave interferometry to study sub Hertz variations of the strain tensor of space-time and gravitation. Using a set of atomic interferometers simultaneously manipulated by the resonant optical field of a 200 m cavity, the MIGA instrument will allow the monitoring of the evolution of the gravitational field at unprecedented sensitivity, which will be exploited both for geophysical studies and for Gravitational Waves (GWs detection. This new infrastructure will be embedded into the LSBB underground laboratory, ideally located away from major anthropogenic disturbances and benefitting from very low background noise.
Supramolecular Soft Matter Applications in Materials and Organic Electronics
Nakanishi, Takashi
2011-01-01
The pivotal text that bridges the gap between fundamentals and applications of soft matter in organic electronics Covering an expanding and highly coveted subject area, Supramolecular Soft Matter enlists the services of leading researchers to help readers understand and manipulate the electronic properties of supramolecular soft materials for use in organic opto-electronic devices, such as photovoltaics and field effect transistors, some of the most desired materials for energy conservation. Rather than offering a compilation of current trends in supramolecular soft matter, this book bridges
Dissipative phenomena in condensed matter some applications
Dattagupta, Sushanta
2004-01-01
From the field of nonequilibrium statistical physics, this graduate- and research-level volume treats the modeling and characterization of dissipative phenomena. A variety of examples from diverse disciplines like condensed matter physics, materials science, metallurgy, chemical physics etc. are discussed. Dattagupta employs the broad framework of stochastic processes and master equation techniques to obtain models for a wide range of experimentally relevant phenomena such as classical and quantum Brownian motion, spin dynamics, kinetics of phase ordering, relaxation in glasses, dissipative tunneling. It provides a pedagogical exposition of current research material and will be useful to experimentalists, computational physicists and theorists.
Holographic geometries for condensed matter applications
Keranen, V
2013-01-01
Holographic modeling of strongly correlated many-body systems motivates the study of novel spacetime geometries where the scaling behavior of quantum critical systems is encoded into spacetime symmetries. Einstein-Dilaton-Maxwell theory has planar black brane solutions that exhibit Lifshitz scaling and in some cases hyperscaling violation. Entanglement entropy and Wilson loops in the dual field theory are studied by inserting simple geometric probes involving minimal surfaces into the black brane geometry. Coupling to background matter fields leads to interesting low-energy behavior in holographic models, such as U(1) symmetry breaking and emergent Lifshitz scaling.
Kadlecová, Hedvika; Weber, Stefan; Korn, Georg
2016-01-01
We analyze theoretical models of gravitational waves generation in the interaction of high intensity laser with matter, namely ablation and piston models. We analyse the generated gravitational waves in linear approximation of gravitational theory. We derive the analytical formulas and estimates for the metric perturbations and the radiated power of generated gravitational waves. Furthermore we investigate the characteristics of polarization and the behaviour of test particles in the presence of gravitational wave which will be important for the detection.
2012-02-10
... Federal Energy Regulatory Commission Green Wave Mendocino Wave Park; Notice of Preliminary Permit... September 23, 2011, Green Wave Energy Solutions, LLC, California, filed an application for a preliminary... the Green Wave Mendocino Wave Park (Mendocino Wave Project or project) to be located in the...
New prospects and techniques for matter wave interferometry with ions
Schütz, Georg; Pooch, Andreas; Schneeweiss, Philipp; Rauschenbeutel, Arno; Hwang, Ing-Shouh; Stibor, Alexander
2013-01-01
We present new developments and potential applications for the first ion-interferometer realized by Maier et al. [1-4], that verified at the end of the last century biprism interference and diffraction of 3 keV helium ions. The design of the setup is based on a coherent field emission source, an electrostatically charged biprism wire as a beam splitter and a multi-channel plate detector. However, due to deficiencies of the coherent ion source in the setup of Maier et al., the interference signal was low, therefore long integration times had to be accepted. In addition, the production of a significant uncharged particle radiation produced a high background intensity. The rest of the instrument proved to have excellent electron and ion optical properties and a high mechanical and electrical stability. Here we describe in detail the original setup and the major innovations to overcome the deficiencies. We introduce a novel single-atom metal tip [5] as a stable, coherent and monochromatic field emission ion sourc...
Dual matter-wave inertial sensors in weightlessness
Barrett, Brynle; Antoni-Micollier, Laura; Chichet, Laure; Battelier, Baptiste; Lévèque, Thomas; Landragin, Arnaud; Bouyer, Philippe
2016-12-01
Quantum technology based on cold-atom interferometers is showing great promise for fields such as inertial sensing and fundamental physics. However, the finite free-fall time of the atoms limits the precision achievable on Earth, while in space interrogation times of many seconds will lead to unprecedented sensitivity. Here we realize simultaneous 87Rb-39K interferometers capable of operating in the weightless environment produced during parabolic flight. Large vibration levels (10-2 g Hz-1/2), variations in acceleration (0-1.8 g) and rotation rates (5° s-1) onboard the aircraft present significant challenges. We demonstrate the capability of our correlated quantum system by measuring the Eötvös parameter with systematic-limited uncertainties of 1.1 × 10-3 and 3.0 × 10-4 during standard- and microgravity, respectively. This constitutes a fundamental test of the equivalence principle using quantum sensors in a free-falling vehicle. Our results are applicable to inertial navigation, and can be extended to the trajectory of a satellite for future space missions.
Gravitational waves in Fully Constrained Formulation in a dynamical spacetime with matter content
Cordero-Carrion, Isabel; Cerda-Duran, Pablo [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85741, Garching (Germany); Ibanez, Jose MarIa, E-mail: chabela@mpa-garching.mpg.de, E-mail: cerda@mpa-garching.mpg.de, E-mail: jose.m.ibanez@uv.es [Departamento de AstronomIa y Astrofisica, Universidad de Valencia, C/ Dr. Moliner 50, E-46100 Burjassot, Valencia (Spain)
2011-09-22
We analyze numerically the behaviour of the hyperbolic sector of the Fully Constrained Formulation (FCF) (Bonazzola et al. 2004). The numerical experiments allow us to be confident in the performances of the upgraded version of the CoCoNuT code (Dimmelmeier et al. 2005) by replacing the Conformally Flat Condition (CFC), an approximation of Einstein equations, by FCF. First gravitational waves in FCF in a dynamical spacetime with matter content will be shown.
From quantum turbulence to statistical atom optics: new perspectives in speckle matter wave
Tavares, P E S; Telles, G D; Impens, F; Kaiser, R; Bagnato, V S
2016-01-01
Quantum Turbulence, the chaotic configuration of tangled quantized vortex lines, can be analyzed from the matter wave perspective in instead of the traditional fluid perspective. We report the observation of a remarkable similarity in between the dynamics of a freely expanding turbulent Bose-Einstein condensate and the propagation of an optical speckle pattern. Both follow very similar basic propagation characteristics. The second-order correlation is calculated and the typical correlation length of the two phenomena is used to substantiate the observations. The analogy between an expanding turbulent atomic condensate and a traveling optical speckle creates exciting prospects to investigate disordered quantum matter including the possibilities of a 3D speckle matter field.
Statistical mechanics and applications in condensed matter
Di Castro, Carlo
2015-01-01
This innovative and modular textbook combines classical topics in thermodynamics, statistical mechanics and many-body theory with the latest developments in condensed matter physics research. Written by internationally renowned experts and logically structured to cater for undergraduate and postgraduate students and researchers, it covers the underlying theoretical principles and includes numerous problems and worked examples to put this knowledge into practice. Three main streams provide a framework for the book; beginning with thermodynamics and classical statistical mechanics, including mean field approximation, fluctuations and the renormalization group approach to critical phenomena. The authors then examine quantum statistical mechanics, covering key topics such as normal Fermi and Luttinger liquids, superfluidity and superconductivity. Finally, they explore classical and quantum kinetics, Anderson localization and quantum interference, and disordered Fermi liquids. Unique in providing a bridge between ...
Gravitational wave signals of electroweak phase transition triggered by dark matter
Chao, Wei; Guo, Huai-Ke; Shu, Jing
2017-09-01
We study in this work a scenario that the universe undergoes a two step phase transition with the first step happened to the dark matter sector and the second step being the transition between the dark matter and the electroweak vacuums, where the barrier between the two vacuums, that is necessary for a strongly first order electroweak phase transition (EWPT) as required by the electroweak baryogenesis mechanism, arises at the tree-level. We illustrate this idea by working with the standard model (SM) augmented by a scalar singlet dark matter and an extra scalar singlet which mixes with the SM Higgs boson. We study the conditions for such pattern of phase transition to occur and especially for the strongly first order EWPT to take place, as well as its compatibility with the basic requirements of a successful dark matter, such as observed relic density and constraints of direct detections. We further explore the discovery possibility of this pattern EWPT by searching for the gravitational waves generated during this process in spaced based interferometer, by showing a representative benchmark point of the parameter space that the generated gravitational waves fall within the sensitivity of eLISA, DECIGO and BBO.
Ahn, Young Kwan; Lee, Hyung Jin; Kim, Yoon Young
2017-08-30
Conical refraction, which is quite well-known in electromagnetic waves, has not been explored well in elastic waves due to the lack of proper natural elastic media. Here, we propose and design a unique anisotropic elastic metamaterial slab that realizes conical refraction for horizontally incident longitudinal or transverse waves; the single-mode wave is split into two oblique coupled longitudinal-shear waves. As an interesting application, we carried out an experiment of parallel translation of an incident elastic wave system through the anisotropic metamaterial slab. The parallel translation can be useful for ultrasonic non-destructive testing of a system hidden by obstacles. While the parallel translation resembles light refraction through a parallel plate without angle deviation between entry and exit beams, this wave behavior cannot be achieved without the engineered metamaterial because an elastic wave incident upon a dissimilar medium is always split at different refraction angles into two different modes, longitudinal and shear.
P-wave Annihilating Dark Matter from a Decaying Predecessor and the Galactic Center Excess
Choquette, Jeremie; Cornell, Jonathan M
2016-01-01
Dark matter (DM) annihilations have been widely studied as a possible explanation of excess gamma rays from the galactic center seen by Fermi/LAT. However most such models are in conflict with constraints from dwarf spheroidals. Motivated by this tension, we show that p-wave annihilating dark matter can easily accommodate both sets of observations due to the lower DM velocity dispersion in dwarf galaxies. Explaining the DM relic abundance is then challenging. We outline a scenario in which the usual thermal abundance is obtained through s-wave annihilations of a metastable particle, that eventually decays into the p-wave annihilating DM of the present epoch. The couplings and lifetime of the decaying particle are constrained by big bang nucleosynthesis, the cosmic microwave background and direct detection, but significant regions of parameter space are viable. A sufficiently large p-wave cross section can be found by annihilation into light mediators, that also give rise to Sommerfeld enhancement. A predictio...
Fourth American Physical Society Topical Conference on Shock Waves in Condensed Matter
Shock Waves in Condensed Matter
1986-01-01
The Fourth American Physical Society Topical Conference on Shock Waves in Condensed Matter was held in Spokane, Washington, July 22-25, 1985. Two hundred and fifty scientists and engineers representing thirteen countries registered at the conference. The countries represented included the United States of America, Australia, Canada, The People's Repub lic of China, France, India, Israel, Japan, Republic of China (Taiwan), United Kingdom, U. S. S. R, Switzerland and West Germany. One hundred and sixty-two technical papers, cov ering recent developments in shock wave and high pressure physics, were presented. All of the abstracts have been published in the September 1985 issue of the Bulletin of the American Physical Society. The topical conferences, held every two years since 1979, have become the principal forum for shock wave studies in condensed materials. Both formal and informal technical discussions regarding recent developments conveyed a sense of excitement. Consistent with the past conferences, th...
Shock wave driven microparticles for pharmaceutical applications
Menezes, V.; Takayama, K.; Gojani, A.; Hosseini, S. H. R.
2008-10-01
Ablation created by a Q-switched Nd:Yttrium Aluminum Garnet (Nd:YAG) laser beam focusing on a thin aluminum foil surface spontaneously generates a shock wave that propagates through the foil and deforms it at a high speed. This high-speed foil deformation can project dry micro- particles deposited on the anterior surface of the foil at high speeds such that the particles have sufficient momentum to penetrate soft targets. We used this method of particle acceleration to develop a drug delivery device to deliver DNA/drug coated microparticles into soft human-body targets for pharmaceutical applications. The device physics has been studied by observing the process of particle acceleration using a high-speed video camera in a shadowgraph system. Though the initial rate of foil deformation is over 5 km/s, the observed particle velocities are in the range of 900-400 m/s over a distance of 1.5-10 mm from the launch pad. The device has been tested by delivering microparticles into liver tissues of experimental rats and artificial soft human-body targets, modeled using gelatin. The penetration depths observed in the experimental targets are quite encouraging to develop a future clinical therapeutic device for treatments such as gene therapy, treatment of cancer and tumor cells, epidermal and mucosal immunizations etc.
Application of MM wave therapy in radiology
Avakian, R.S. [Inst. of Radio Physics & Electronics, Ashtarack (Argentina); Gasparyan, L.V. [Republican Medical Centre Armenia, Yerevan (Argentina)
1995-12-31
The authors studied the effects of MM wave electromagnetic radiation influence on patients, affected by X-ray radiation during the reparation works after Chernobyl nuclear power plant exposure. They compared results of treatment of two groups of patients: (1) control group patients received only basis therapy; (2) testing group, 10 patients received basis therapy and MM wave influence. The authors used the wide band noise generator `Artsakh - 2` for local irradiation on the acupuncture points. Their data proved that low intensity MM waves have immunocorrective, antioxidant effects, and MM wave therapy is a perspective method for treatment of patients with radiological pathology.
Aperiodic structures in condensed matter fundamentals and applications
Macia Barber, Enrique
2008-01-01
One of the Top Selling Physics Books according to YBP Library ServicesOrder can be found in all the structures unfolding around us at different scales, including in the arrangements of matter and in energy flow patterns. Aperiodic Structures in Condensed Matter: Fundamentals and Applications focuses on a special kind of order referred to as aperiodic order.The book covers several topics dealing with the role of aperiodic order in numerous domains of the physical sciences and technology. It first presents the most characteristic features of various aperiodic systems. The author then describes t
An Overview of Millimeter Wave Communications for Military Applications
A. S. Bains
1993-01-01
Full Text Available The use of millimeter wave for Defence communications can offer a number of benefits to the user. Apart from the benefit of wider capacity, millimeter wave also offers ability to provide secure and survivable communication in the presence of enemy threats. In this paper, some of the important benefits for Defence communication are reviewed. An overview of millimeter wave military communication applications, technology development, present status and trends are also given.
Millimeter-wave/THz FMCW radar techniques for sensing applications
Mirando, D. Amal; Higgins, Michael D.; Wang, Fenggui; Petkie, Douglas T.
2016-10-01
Millimeter-wave and terahertz continuous-wave radar systems have been used to measure physiological signatures for biometric applications and for a variety of non-destructive evaluation applications, such as the detection of defects in materials. Sensing strategies for the simplest homodyne systems, such as a Michelson Interferometer, can be enhanced by using Frequency Modulated Continuous Wave (FMCW) techniques. This allows multiple objects or surfaces to be range resolved while monitoring the phase of the signal in a particular range bin. We will discuss the latest developments in several studies aimed at demonstrating how FMCW techniques can enhance mmW/THz sensing applications.
Dark Matter searches using gravitational wave bar detectors: quark nuggets and newtorites
Bassan, M; D'Antonio, S.; Fafone, V.; Giordano, G.; Marini, A.; Minenkov, Y.; Modena, I.; Pallottino, G.V.; Pizzella, G.; Rocchi, A.; Ronga, F.; Visco, M.
2016-01-01
Many experiments have searched for supersymmetric WIMP dark matter, with null results. This may suggest to look for more exotic possibilities, for example compact ultra-dense quark nuggets, widely discussed in literature with several different names. Nuclearites are an example of candidate compact objects with atomic size cross section. After a short discussion on nuclearites, the result of a nuclearite search with the gravitational wave bar detectors Nautilus and Explorer is reported. The geometrical acceptance of the bar detectors is 19.5 $\\rm m^2$ sr, that is smaller than that of other detectors used for similar searches. However, the detection mechanism is completely different and is more straightforward than in other detectors. The experimental limits we obtain are of interest because, for nuclearites of mass less than $10^{-5}$ g, we find a flux smaller than that one predicted considering nuclearites as dark matter candidates. Particles with gravitational only interactions (newtorites) are another examp...
Chala, Mikael [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Nardini, Germano [Bern Univ. (Switzerland). Inst. for Theoretical Physics; Sobolev, Ivan [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Moscow State Univ. (Russian Federation). Dept. of Particle Physics and Cosmology
2016-05-15
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset SO(7)/SO(6). We show that by embedding the elementary fermions in appropriate representations of SO(7), all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new CP-violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark matter direct detection and gravitational wave experiments.
Chala, Mikael; Nardini, Germano; Sobolev, Ivan
2016-09-01
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset S O (7 )/S O (6 ). We show that by embedding the elementary fermions in appropriate representations of S O (7 ), all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new C P -violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark matter direct detection and gravitational wave experiments.
Gravitational Waves as a New Probe of Bose-Einstein Condensate Dark Matter
Dev, P S Bhupal; Ohmer, Sebastian
2016-01-01
There exists a class of ultralight Dark Matter (DM) models which could form a Bose-Einstein condensate (BEC) in the early universe and behave as a single coherent wave instead of individual particles in galaxies. We show that a generic BEC DM halo intervening along the line of sight of a gravitational wave (GW) signal could induce an observable change in the speed of GW, with the effective refractive index depending only on the mass and self-interaction of the constituent DM particles and the GW frequency. Hence, we propose to use the deviation in the speed of GW as a new probe of the BEC DM parameter space. With a multi-messenger approach to GW astronomy and/or with extended sensitivity to lower GW frequencies, the entire BEC DM parameter space can be effectively probed by our new method in the near future.
Canuel, B; Amand, L; Bertoldi, A; Cormier, E; Fang, B; Gaffet, S; Geiger, R; Harms, J; Holleville, D; Landragin, A; Lefèvre, G; Lhermite, J; Mielec, N; Prevedelli, M; Riou, I; Bouyer, P
2016-01-01
The Matter-Wave laser Interferometer Gravitation Antenna, MIGA, will be a hybrid instrument composed of a network of atom interferometers horizontally aligned and interrogated by the resonant field of an optical cavity. This detector will provide measurements of sub Hertz variations of the gravitational strain tensor. MIGA will bring new methods for geophysics for the characterization of spatial and temporal variations of the local gravity field and will also be a demonstrator for future low frequency Gravitational Wave (GW) detections. MIGA will enable a better understanding of the coupling at low frequency between these different signals. The detector will be installed underground in Rustrel (FR), at the "Laboratoire Souterrain Bas Bruit" (LSBB), a facility with exceptionally low environmental noise and located far away from major sources of anthropogenic disturbances. We give in this paper an overview of the operating mode and status of the instrument before detailing simulations of the gravitational backg...
Canuel, B.; Pelisson, S.; Amand, L.; Bertoldi, A.; Cormier, E.; Fang, B.; Gaffet, S.; Geiger, R.; Harms, J.; Holleville, D.; Landragin, A.; Lefèvre, G.; Lhermite, J.; Mielec, N.; Prevedelli, M.; Riou, I.; Bouyer, P.
2016-04-01
The Matter-Wave laser Interferometer Gravitation Antenna, MIGA, will be a hybrid instrument composed of a network of atom interferometers horizontally aligned and interrogated by the resonant field of an optical cavity. This detector will provide measurements of sub Hertz variations of the gravitational strain tensor. MIGA will bring new methods for geophysics for the characterization of spatial and temporal variations of the local gravity field and will also be a demonstrator for future low frequency Gravitational Wave (GW) detections. MIGA will enable a better understanding of the coupling at low frequency between these different signals. The detector will be installed underground in Rustrel (FR), at the "Laboratoire Souterrain Bas Bruit" (LSBB), a facility with exceptionally low environmental noise and located far away from major sources of anthropogenic disturbances. We give in this paper an overview of the operating mode and status of the instrument before detailing simulations of the gravitational background noise at the MIGA installation site.
Collisional-inhomogeneity-induced generation of matter-wave dark solitons
Wang, C. [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Kevrekidis, P.G., E-mail: kevrekid@gmail.co [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Horikis, T.P. [Department of Mathematics, University of Ioannina, Ioannina 45110 (Greece); Frantzeskakis, D.J. [Department of Physics, University of Athens, Panepistimiopolis, Zografos, Athens 15784 (Greece)
2010-08-16
We propose an experimentally relevant protocol for the controlled generation of matter-wave dark solitons in atomic Bose-Einstein condensates (BECs). In particular, using direct numerical simulations, we show that by switching-on a spatially inhomogeneous (step-like) change of the s-wave scattering length, it is possible to generate a controllable number of dark solitons in a quasi-one-dimensional BEC. A similar phenomenology is also found in the two-dimensional setting of 'disk-shaped' BECs but, as the solitons are subject to the snaking instability, they decay into vortex structures. A detailed investigation of how the parameters involved affect the emergence and evolution of solitons and vortices is provided.
Gomes Rossin, Bruna; Redon, Roland; Raynaud, Michel; Nascimento, Nadia Regina; Mounier, Stéphane
2017-04-01
amazonien. [PHD] .Universidade Estadual Paulista "Júlio de Mesquita Filho";2009. Monakhova, Yulia B., Alexey M. Tsikin, Svetlana P. Mushtakova, and Mauro Mecozzi. 2015. "Independent Component Analysis and Multivariate Curve Resolution to Improve Spectral Interpretation of Complex Spectroscopic Data Sets: Application to Infrared Spectra of Marine Organic Matter Aggregates." Microchemical Journal, Devoted to the Application of Microtechniques in All Branches of Science 118 (January): 211-22. Tadini, Amanda Maria, Gustavo Nicolodelli, Stephane Mounier, Célia Regina Montes, and Débora Marcondes Bastos Pereira Milori. 2015. "The Importance of Humin in Soil Characterisation: A Study on Amazonian Soils Using Different Fluorescence Techniques." The Science of the Total Environment 537 (December): 152-58.
Submillimeter-Wave Radiometer Technology for Earth Remote Sensing Applications
Siegel, P.
2000-01-01
Recent innovations in ultra-high frequency, semiconductor device/component technology have enabled both traditional and new applications for space-borne millimeter- and submillimeter-wave heterodyne radiometer instruments.
Potential applications of microstrip devices with traveling wave resonators
Glushechenko E. N.
2013-05-01
Full Text Available The shortcomings of the known microwave filters in microstrip lines are considered, the advantages of the use of directional traveling-wave filters in microstrip performance and examples of their potential applications are shown.
Time-Reversal of Nonlinear Waves - Applicability and Limitations
Ducrozet, G; Chabchoub, A
2016-01-01
Time-reversal (TR) refocusing of waves is one of fundamental principles in wave physics. Using the TR approach, "Time-reversal mirrors" can physically create a time-reversed wave that exactly refocus back, in space and time, to its original source regardless of the complexity of the medium as if time were going backwards. Lately, laboratory experiments proved that this approach can be applied not only in acoustics and electromagnetism but also in the field of linear and nonlinear water waves. Studying the range of validity and limitations of the TR approach may determine and quantify its range of applicability in hydrodynamics. In this context, we report a numerical study of hydrodynamic TR using a uni-directional numerical wave tank, implemented by the nonlinear high-order spectral method, known to accurately model the physical processes at play, beyond physical laboratory restrictions. The applicability of the TR approach is assessed over a variety of hydrodynamic localized and pulsating structures' configu...
Generalized calculus with applications to matter and forces
Campos, L M B C
2014-01-01
Combining mathematical theory, physical principles, and engineering problems, Generalized Calculus with Applications to Matter and Forces examines generalized functions, including the Heaviside unit jump and the Dirac unit impulse and its derivatives of all orders, in one and several dimensions. The text introduces the two main approaches to generalized functions: (1) as a nonuniform limit of a family of ordinary functions, and (2) as a functional over a set of test functions from which properties are inherited. The second approach is developed more extensively to encompass multidimensional generalized functions whose arguments are ordinary functions of several variables. As part of a series of books for engineers and scientists exploring advanced mathematics, Generalized Calculus with Applications to Matter and Forces presents generalized functions from an applied point of view, tackling problem classes such as: •Gauss and Stokes’ theorems in the differential geometry, tensor calculus, and theory of ...
Applications of lattice QCD techniques for condensed matter systems
Buividovich, P. V.; Ulybyshev, M. V.
2016-08-01
We review the application of lattice QCD techniques, most notably the Hybrid Monte Carlo (HMC) simulations, to first-principle study of tight-binding models of crystalline solids with strong inter-electron interactions. After providing a basic introduction into the HMC algorithm as applied to condensed matter systems, we review HMC simulations of graphene, which in the recent years have helped to understand the semimetal behavior of clean suspended graphene at the quantitative level. We also briefly summarize other novel physical results obtained in these simulations. Then we comment on the applicability of hybrid Monte Carlo to topological insulators and Dirac and Weyl semimetals and highlight some of the relevant open physical problems. Finally, we also touch upon the lattice strong-coupling expansion technique as applied to condensed matter systems.
Matter-wave propagation in optical lattices: geometrical and flat-band effects
Metcalf, Mekena; Chern, Gia-Wei; Di Ventra, Massimiliano; Chien, Chih-Chun
2016-04-01
The geometry of optical lattices can be engineered, allowing the study of atomic transport along paths arranged in patterns that are otherwise difficult to probe in the solid state. A question feasible to atomic systems is related to the speed of matter-wave propagation as a function of the lattice geometry. To address this issue, we investigated, theoretically, the quantum transport of noninteracting and weakly-interacting ultracold fermionic atoms in several 2D optical lattice geometries. We find that the triangular lattice has a higher propagation velocity compared to the square lattice, and the cross-linked square lattice has an even faster propagation velocity. The increase results from the mixing of the momentum states which leads to different group velocities in quantum systems. Standard band theory provides an explanation and allows for a systematic way to search and design systems with controllable matter-wave propagation. Moreover, the presence of a flat band such as in a two-leg ladder geometry leads to a dynamical density discontinuity due to its localized atoms. Possible realizations of those dynamical phenomena are discussed.
Black holes and gravitational waves in models of minicharged dark matter
Cardoso, Vitor; Pani, Paolo; Ferrari, Valeria
2016-01-01
In viable models of minicharged dark matter, astrophysical black holes might be charged under a hidden $U(1)$ symmetry and are formally described by the same Kerr-Newman solution of Einstein-Maxwell theory. These objects are unique probes of minicharged dark matter and dark photons. We show that the recent gravitational-wave detection of a binary black-hole coalescence by aLIGO provides various observational bounds on the black hole's charge, regardless of its nature. The pre-merger inspiral phase can be used to constrain the dipolar emission of (ordinary and dark) photons, whereas the detection of the quasinormal modes set an upper limit on the final black hole's charge. By using a toy model of a point charge plunging into a Reissner-Nordstrom black hole, we also show that in dynamical processes the (hidden) electromagnetic quasinormal modes of the final object are excited to considerable amplitude in the gravitational-wave spectrum only when the black hole is nearly extremal. The coalescence produces a burs...
Repeated application of organic waste affects soil organic matter composition
Peltre, Clément; Gregorich, Edward G.; Bruun, Sander
2017-01-01
of different types of carbon compounds in soil. The objective of this study was to identify and characterise changes in soil organic matter (SOM) composition after repeated applications of organic waste. Soil from the CRUCIAL field experiment in Denmark was sampled after 12 years of annual application...... that there was accumulation in soil of different C compounds for the different types of applied organic waste, which appeared to be related to the degree to which microbial activity was stimulated and the type of microbial communities applied with the wastes or associated with the decomposition of applied wastes...
[Extracorporeal shock-wave therapy. Experimental basis, clinical application].
Rompe, J D; Küllmer, K; Vogel, J; Eckardt, A; Wahlmann, U; Eysel, P; Hopf, C; Kirkpatrick, C J; Bürger, R; Nafe, B
1997-03-01
The purpose of our studies was to investigate experimentally the dose-dependent effects of extracorporeal shock waves on tendon and bone and to unveil therapeutic possibilities in tendinopathies and pseudarthroses. In animal experiments, both positive and negative influences were exerted by shock waves, depending on the initial situation and on the power of the applied shock waves. In prospective clinical trials positive effects were found in the treatment of persistent tennis elbow, plantar fasciitis, calcifying tendinitis, and pseudarthrosis. Our data show that extracorporeal shock waves may provide analgesic, resorptive and osteo-inductive reactions with nearly no side effects. However, the high cost of apparatus and staff prevents a routine application. Extracorporeal shock waves thus remain a last alternative before the indication is made for an operative procedure.
López-Ruiz, Alejandro; Solari, Sebastián; Ortega-Sánchez, Miguel; Losada, Miguel
2015-12-01
This work presents a simple and relatively quick methodology to obtain the nearshore wave angle. The method is especially valuable for curvilinear coasts where Snell's law may provide excessively inaccurate results. We defined a correction factor, K, that depends on the geometry of the coast and on the wave climate. The values of this coefficient were obtained minimizing the differences with a sophisticated numerical model. The limitations and performance of the methodology are further discussed. The procedure was applied to a beach in Southern Spain to analyze the influence of shoreline geometry on nearshore wave directionality. Offshore and nearshore distributions of wave period and directions were analyzed, and the results showed that the geometry of the coast played a crucial role in the directionality of the nearshore waves, which also plays an important role in hydrodynamics. The methodology presented here is able to analyze and quantify the importance of this directionality without a noticeable computational cost, even when a long time series of wave data are considered. Hence, this methodology constitutes a useful and efficient tool for practical applications in Coastal and Ocean Engineering, such as sedimentary, wave energy, and wave climate studies.
Barenboim, Gabriela, E-mail: Gabriela.Barenboim@uv.es; Park, Wan-Il, E-mail: Wanil.Park@uv.es
2016-08-10
We investigate the gravitational wave background from a first order phase transition in a matter-dominated universe, and show that it has a unique feature from which important information about the properties of the phase transition and thermal history of the universe can be easily extracted. Also, we discuss the inverse problem of such a gravitational wave background in view of the degeneracy among macroscopic parameters governing the signal.
Farghaly, Othman A; Ghandour, M A
2005-03-01
The application of square-wave voltammetry (SWV) for the determination of eight elements viz. Cd(II), Pb(II), Cu(II), Zn(II), Co(II), Ni(II), Cr(VI), and Mo(VI) in soil and indoor-airborne particulate matter has been examined and optimized. The cathodic and anodic types of the SWV technique were examined for the detection of these metal ions. It was found that the square-wave anodic stripping voltammetry is the conventional technique for the determination of Zn(II), Cd(II), Pb(II), and Cu(II), but square-wave adsorptive cathodic stripping voltammetric method is used for the determination of Co(II), Ni(II), Mo(VI) and Cr(VI). Various experimental parameters, which influenced the response of the mercury film electrode to these metal ions, were optimized. The detection limits of these metal ions were 0.03, 0.4, 0.04, 0.1, 0.15, 0.05, 0.2, and 3.2 microg/kg for Cd(II), Pb(II), Cu(II), Zn(II), Co(II), Ni(II), Cr(VI), and Mo(VI), respectively, with very good accuracy (standard deviation is below 2%). Interference from coexisting ions was successfully investigated. A comparison of analytical data for analyzing real samples was carried out between the SWV method and the graphite furnace atomic absorption spectrophotometric (GFAAS) method. By the standard addition method, the recoveries were 96.6-104% with SD of 0.75-2.5%. The great advantage of SWV is the simplicity, selectivity, sensitivity, and shortening analysis time over the GFAAS method.
Application of LCR Waves to Inspect Aircraft Structures
2013-01-01
Mechanical Engineering (COBEM 2011). Proceedings of COBEM, 2011. Natal, RN, Brasil Analysis of the behavior of Lcr Waves propagating in Steel bars using...Taguchi Method. 21 th International Congress of Mechanical Engineering (COBEM 2011). Proceedings of COBEM, 2011. Natal, RN, Brasil . Application...of Design of Experiments to Evaluation the Propagation Speed of Lcr Waves. 5 th Pan American Conference for NDT, 2011. Cancum, Mexico . Proceedings of
Slowly moving matter-wave gap soliton propagation in weak random nonlinear potential
Zhang Ming-Rui; Zhang Yong-Liang; Jiang Xun-Ya; Zi Jian
2008-01-01
We systematically investigate the motion of slowly moving matter-wave gap solitons in a nonlinear potential, produced by the weak random spatial variation of the atomic scattering length. With the weak randomness, we construct an effective-particle theory to study the motion of gap solitons. Based on the effective-particle theory, the effect of the randomness on gap solitous is obtained, and the motion of gap solitons is finally solved. Moreover, the analytic results for the general behaviours of gap soliton motion, such as the ensemble-average speed and the reflection probability depending on the weak randomness are obtained. We find that with the increase of the random strength the ensemble-average speed of gap solitons decreases slowly where the reduction is proportional to the variance of the weak randomness, and the reflection probability becomes larger. The theoretical results are in good agreement with the numerical simulations based on the Gross-Pitaevskii equation.
Evolution of Matter Wave Interference of Bose-Condensed Gas in a 1D Optical Lattice
XU Zhi-Jun; ZHANG Dong-Mei
2007-01-01
For a Bose-condensed gas in a combined potential consisting of an axially-symmetric harmonic magnetic trap and one-dimensional (1D) optical lattice, using the mean-field Gross-Pitaevskii (G-P) equation and the propagator method, we obtain the analytical result of the order parameter for matter wave interference at any time. The evolution of the interference pattern under a variation of the relative phase △φ between successive subcondensates trapped on an optical lattices is also studied. For △φ = π, the interference pattern is symmetric with two sharp peaks, which are symmetrically located on a straight line on both sides of a vacant central peak and moving apart from each other. This work is in agreement with available experimental results.
Matter-wave soliton bouncing on a reflecting surface under the effect of gravity
Benseghir, A.; Abdullah, W. A. T. Wan; Baizakov, B. B.; Abdullaev, F. Kh.
2014-08-01
The dynamics of a matter-wave soliton bouncing on the reflecting surface (atomic mirror) under the effect of gravity has been studied by analytical and numerical means. The analytical description is based on the variational approach. Resonant oscillations of the soliton's center of mass and width, induced by appropriate modulation of the atomic scattering length and the slope of the linear potential, are analyzed. In numerical experiments we observe the Fermi-type acceleration of the soliton when the vertical position of the reflecting surface is periodically varied in time. Analytical predictions are compared to the results of numerical simulations of the Gross-Pitaevskii equation and qualitative agreement between them is found.
Quantum reflection of bright solitary matter-waves from a narrow attractive potential
Marchant, A L; Yu, M M H; Rakonjac, A; Helm, J L; Polo, J; Weiss, C; Gardiner, S A; Cornish, S L
2015-01-01
We report the observation of quantum reflection from a narrow, attractive, potential using bright solitary matter-waves formed from a 85Rb Bose-Einstein condensate. We create narrow potentials using a tightly focused, red-detuned laser beam, and observe reflection of up to 25% of the atoms, along with the trapping of atoms at the position of the beam. We show that the observed reflected fraction is much larger than theoretical predictions for a narrow Gaussian potential well; a more detailed model of bright soliton propagation, accounting for the generic presence of small subsidiary intensity maxima in the red-detuned beam, suggests that these small intensity maxima are the cause of this enhanced reflection.
Escape of a vector matter-wave soliton from a parabolic trap
Bludov, Yuliy V.; García-Ñustes, Monica A.
2017-07-01
We show that a vector matter-wave soliton in a Bose-Einstein condensate (BEC) loaded into an optical lattice can escape from a trap formed by a parabolic potential, resembling a Hawking emission. The particle-antiparticle pair is emulated by a low-amplitude bright-bright soliton in a two-component BEC with effective masses of opposite signs. It is shown that the parabolic potential leads to a spatial separation of BEC components. One component with chemical potential in a semi-infinite gap exerts periodical oscillations, while the other BEC component, with negative effective mass, escapes from the trap. The mechanism of atom transfer from one BEC component to another by spatially periodic linear coupling term is also discussed.
Aquatic Organic Matter Fluorescence - from phenomenon to application
Reynolds, Darren
2014-05-01
The use of fluorescence to quantify and characterise aquatic organic matter in river, ocean, ground water and drinking and waste waters has come along way since its discovery as a phenomenon in the early 20th century. For example, there are over 100 papers published each year in international peer reviewed journals, an order of magnitude increase since a decade ago (see Figure taken from ISI database from 1989 to 2007 for publications in the fields of river water and waste water). Since then it has been extensively used as a research tool since the 1990's by scientists and is currently used for a wide variety of applications within a number of sectors. Universities, organisations and companies that research into aquatic organic matter have either recently readily use appropriate fluorescence based techniques and instrumentation. In industry and government, the technology is being taken up by environmental regulators and water and wastewater companies. This keynote presentation will give an overview of aquatic organic matter fluorescence from its conception as a phenomenon through to its current use in a variety of emerging applications within the sectors concerned with understanding, managing and monitoring the aquatic environment. About the Speaker Darren Reynolds pioneered the use of fluorescence spectroscopy for the analysis of wastewaters in the 1990's. He currently leads a research group within the Centre for Research in Biosciences and sits on the Scientific Advisory Board for the Institute of Bio-Sensing Technology at the University of the West of England, Bristol. He is a multidisciplinary scientist concerned with the development of technology platforms for applications in the fields of environment/agri-food and health. His current research interests include the development of optical technologies and techniques for environmental and biological sensing and bio-prospecting applications. He is currently involved in the development and use of synthetic biology
48 CFR 27.203 - Security requirements for patent applications containing classified subject matter.
2010-10-01
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Security requirements for patent applications containing classified subject matter. 27.203 Section 27.203 Federal Acquisition... subject matter....
The role of the wave function in the GRW matter density theory
Egg, Matthias [University of Lausanne (Switzerland)
2014-07-01
Every approach to quantum mechanics postulating some kind of primitive ontology (e.g., Bohmian particles, a mass density field or flash-like collapse events) faces the challenge of clarifying the ontological status of the wave function. More precisely, one needs to spell out in what sense the wave function ''governs'' the behaviour of the primitive ontology, such that the empirical predictions of standard quantum mechanics are recovered. For Bohmian mechanics, this challenge has been addressed in recent papers by Belot and Esfeld et al. In my talk, I do the same for the matter density version of the Ghirardi-Rimini-Weber theory (GRWm). Doing so will highlight relevant similarities and differences between Bohmian mechanics and GRWm. The differences are a crucial element in the evaluation of the relative strengths and weaknesses of the two approaches, while the similarities can shed light on general characteristics of the primitive ontology approach, as opposed to other interpretative approaches to quantum mechanics.
De Broglie's matter-waves are based on a logical bug
Giese, Albrecht
2016-07-01
The postulation of matter waves by Louis de Broglie in 1923 was one of the basic starting points in the development of quantum mechanics. However, his deduction contains a serious logical error. De Broglie deduced his central formula from considerations about the relativistic behaviour of a particle. He saw a conflict in the fact that a particle set into motion increases its internal frequency, f, according to E=h.f, whereas on the other hand its frequency has to decrease due to dilation. To solve this, he assigned a new ''de Broglie wave'' to a particle, which is related to the momentum of the particle. Scattering experiments seemed to confirm this approach. However, if such a scattering process is observed from a moving system, it turns out that the relationship between the wavelength and the momentum yields nonsensical results. - De Broglie's deduction is based on an incorrect understanding of relativity with respect to dilation. We show which results are achieved if a correct understanding is applied. And we show why, in a normal scattering experiment, de Broglie's incorrect formula nevertheless yields the expected results. We will further explain some of the impacts of this error on the equations of Schroedinger and Dirac, who used de Broglie's formula as a starting point. Heisenberg's uncertainty principle is also affected.
Dipolar matter-wave solitons in two-dimensional anisotropic discrete lattices
Chen, Huaiyu; Liu, Yan; Zhang, Qiang; Shi, Yuhan; Pang, Wei; Li, Yongyao
2016-05-01
We numerically demonstrate two-dimensional (2D) matter-wave solitons in the disk-shaped dipolar Bose-Einstein condensates (BECs) trapped in strongly anisotropic optical lattices (OLs) in a disk's plane. The considered OLs are square lattices which can be formed by interfering two pairs of plane waves with different intensities. The hopping rates of the condensates between two adjacent lattices in the orthogonal directions are different, which gives rise to a linearly anisotropic system. We find that when the polarized orientation of the dipoles is parallel to disk's plane with the same direction, the combined effects of the linearly anisotropy and the nonlocal nonlinear anisotropy strongly influence the formations, as well as the dynamics of the lattice solitons. Particularly, the isotropy-pattern solitons (IPSs) are found when these combined effects reach a balance. Motion, collision, and rotation of the IPSs are also studied in detail by means of systematic simulations. We further find that these IPSs can move freely in the 2D anisotropic discrete system, hence giving rise to an anisotropic effective mass. Four types of collisions between the IPSs are identified. By rotating an external magnetic field up to a critical angular velocity, the IPSs can still remain localized and play as a breather. Finally, the influences from the combined effects between the linear and the nonlocal nonlinear anisotropy with consideration of the contact and/or local nonlinearity are discussed too.
Statics and dynamics of a self-bound matter-wave quantum ball
Adhikari, S. K.
2017-02-01
We study the statics and dynamics of a stable, mobile, three-dimensional matter-wave spherical quantum ball created in the presence of an attractive two-body and a very small repulsive three-body interaction. The quantum ball can propagate with a constant velocity in any direction in free space and its stability under a small perturbation is established numerically and variationally. In frontal head-on and angular collisions at large velocities two quantum balls behave like quantum solitons. Such collision is found to be quasielastic and the quantum balls emerge after collision without any change of direction of motion and velocity and with practically no deformation in shape. When reflected by a hard impenetrable plane, the quantum ball bounces off like a wave obeying the law of reflection without any change of shape or speed. However, in a collision at small velocities two quantum balls coalesce to form a larger ball which we call a quantum-ball breather. We point out the similarity and difference between the collision of two quantum and classical balls. The present study is based on an analytic variational approximation and a full numerical solution of the mean-field Gross-Pitaevskii equation using the parameters of 7Li atoms.
Wide-band slow-wave systems simulation and applications
Staras, Stanislovas
2012-01-01
The field of electromagnetics has seen considerable advances in recent years, based on the wide applications of numerical methods for investigating electromagnetic fields, microwaves, and other devices. Wide-Band Slow-Wave Systems: Simulation and Applications presents new technical solutions and research results for the analysis, synthesis, and design of slow-wave structures for modern electronic devices with super-wide pass-bands. It makes available, for the first time in English, significant research from the past 20 years that was previously published only in Russian and Lithuanian. The aut
Schmid, Manfred; Kroupa, Pavel
2014-08-01
We construct an idealised universe for didactic purposes. This universe is assumed to consist of absolute Euclidean space and to be filled with a classical medium which allows for sound waves. A known solution to the wave equation describing the dynamics of the medium is a standing spherical wave. Although this is a problem of classical mechanics, we demonstrate that the Lorentz transformation is required to generate a moving solution from the stationary one. Both solutions are here collectively referred to as "spherons". These spherons exhibit properties which have analogues in the physical description of matter with rest mass, among them de Broglie like phase waves and at the same time "relativistic" effects such as contraction and a speed limit. This leads to a theory of special relativity by assuming the point of view of an observer made of such spheronic "matter". The argument made here may thus be useful as a visualisation or didactic approach to the real universe, in which matter has wave-like properties and obeys the laws of special relativity.
Schmid, Manfred
2014-01-01
We construct an idealized universe for didactic purposes. This universe is assumed to consist of absolute Euclidean space and to be filled with a classical medium which allows for sound waves. A known solution to the wave equation describing the dynamics of the medium is a standing spherical wave. Although this is a problem of classical mechanics, we demonstrate that the Lorentz transformation is required to generate a moving solution from the stationary one. Both solutions are here collectively referred to as "spherons". These spherons exhibit properties which have analogues in the physical description of matter with rest mass, among them de Broglie like phase waves and at the same time "relativistic" effects such as contraction and a speed limit. This leads to a theory of special relativity by assuming the point of view of an observer made of such spheronic "matter". The argument made here may thus be useful as a visualisation or didactic approach to the real universe, in which matter has wave-like properti...
Bastos, Catarina
2016-01-01
In flat spacetime, quantum fluctuations in dark matter, as described as a Bose-Einstein condensate, are stable and display a relativistic Bogoliubov dispersion relation. In the weak gravitational field limit, both relativistic and nonrelativistic models self-gravitating dark matter suggest the formation of structures as the result of a dynamical (Jeans) instability. Here, we show that in the presence of spontaneous symmetry breaking of the dark matter field, the gravitational wave is damped for wave-lengths larger than the Jeans length. Such energy is converted to the Bogoliubov modes of the BEC that in their turn become unstable and grow, leading to the formation of structures even in the absence of expansion. Remarkably, this compensated attenuation/amplification mechanism is the signature of a discrete PT-symmetry-breaking of the system.
Time-reversal of nonlinear waves: Applicability and limitations
Ducrozet, G.; Fink, M.; Chabchoub, A.
2016-09-01
Time-reversal (TR) refocusing of waves is one of the fundamental principles in wave physics. Using the TR approach, time-reversal mirrors can physically create a time-reversed wave that exactly refocus back, in space and time, to its original source regardless of the complexity of the medium as if time were going backward. Laboratory experiments have proved that this approach can be applied not only in acoustics and electromagnetism, but also in the field of linear and nonlinear water waves. Studying the range of validity and limitations of the TR approach may determine and quantify its range of applicability in hydrodynamics. In this context, we report a numerical study of hydrodynamic time-reversal using a unidirectional numerical wave tank, implemented by the nonlinear high-order spectral method, known to accurately model the physical processes at play, beyond physical laboratory restrictions. The applicability of the TR approach is assessed over a variety of hydrodynamic localized and pulsating structures' configurations, pointing out the importance of high-order dispersive and particularly nonlinear effects in the refocusing of hydrodynamic stationary envelope solitons and breathers. We expect that the results may motivate similar experiments in other nonlinear dispersive media and encourage several applications with particular emphasis on the field of ocean engineering.
Continuous-terahertz-wave molecular imaging system for biomedical applications
Zhang, Rui; Zhang, Liangliang; Wu, Tong; Wang, Ruixue; Zuo, Shasha; Wu, Dong; Zhang, Cunlin; Zhang, Jue; Fang, Jing
2016-07-01
Molecular imaging techniques are becoming increasingly important in biomedical research and potentially in clinical practice. We present a continuous-terahertz (THz)-wave molecular imaging system for biomedical applications, in which an infrared (IR) laser is integrated into a 0.2-THz reflection-mode continuous-THz-wave imaging system to induce surface plasmon polaritons on the nanoparticles and further improve the intensity of the reflected signal from the water around the nanoparticles. A strong and rapid increment of the reflected THz signal in the nanoparticle solution upon the IR laser irradiation is demonstrated, using either gold or silver nanoparticles. This low-cost, simple, and stable continuous-THz-wave molecular imaging system is suitable for miniaturization and practical imaging applications; in particular, it shows great promise for cancer diagnosis and nanoparticle drug-delivery monitoring.
Surface acoustic wave devices for sensor applications
Bo, Liu; Xiao, Chen; Hualin, Cai; Mohammad, Mohammad Ali; Xiangguang, Tian; Luqi, Tao; Yi, Yang; Tianling, Ren
2016-02-01
Surface acoustic wave (SAW) devices have been widely used in different fields and will continue to be of great importance in the foreseeable future. These devices are compact, cost efficient, easy to fabricate, and have a high performance, among other advantages. SAW devices can work as filters, signal processing units, sensors and actuators. They can even work without batteries and operate under harsh environments. In this review, the operating principles of SAW sensors, including temperature sensors, pressure sensors, humidity sensors and biosensors, will be discussed. Several examples and related issues will be presented. Technological trends and future developments will also be discussed. Project supported by the National Natural Science Foundation of China (Nos. 60936002, 61025021, 61434001, 61574083), the State Key Development Program for Basic Research of China (No. 2015CB352100), the National Key Project of Science and Technology (No. 2011ZX02403-002) and the Special Fund for Agroscientific Research in the Public Interest of China (No. 201303107). M.A.M is additionally supported by the Postdoctoral Fellowship (PDF) program of the Natural Sciences and Engineering Research Council (NSERC) of Canada and the China Postdoctoral Science Foundation (CPSF).
Massive Primordial Black Holes as Dark Matter and their detection with Gravitational Waves
García-Bellido, Juan
2017-05-01
Massive Primordial Black Holes (MPBH) can be formed after inflation due to broad peaks in the primordial curvature power spectrum that collapse gravitationally during the radiation era, to form clusters of black holes that merge and increase in mass after recombination, generating today a broad mass-spectrum of black holes with masses ranging from 0.01 to 105 M⊙ . These MPBH could act as seeds for galaxies and quick-start structure formation, initiating reionization, forming galaxies at redshift z > 10 and clusters at z > 1. They may also be the seeds on which SMBH and IMBH form, by accreting gas onto them and forming the centers of galaxies and quasars at high redshift. They form at rest with zero spin and have negligible cross-section with ordinary matter. If there are enough of these MPBH, they could constitute the bulk of the Dark Matter today. Such PBH could be responsible for the observed fluctuations in the CIB and X-ray backgrounds. MPBH could be directly detected by the gravitational waves emitted when they merge to form more massive black holes, as recently reported by LIGO. Their continuous merging since recombination could have generated a stochastic background of gravitational waves that could eventually be detected by LISA and PTA. MPBH may actually be responsible for the unidentified point sources seen by Fermi, Magic and Chandra. Furthermore, the ejection of stars from shallow potential wells like those of Dwarf Spheroidals (DSph), via the gravitational slingshot effect, could be due to MPBH, thus alleviating the substructure and too-big-to-fail problems of standard collisionless CDM. Their mass distribution peaks at a few tens of M⊙ today, and could therefore be detected also with long-duration microlensing events, as well as by the anomalous motion of stars in the field of GAIA. Their presence as CDM in the Universe could be seen in the time-dilation of strong-lensing images of quasars. The hierarchical large scale structure behaviour of MPBH
Microwave and millimeter-wave remote sensing for security applications
Nanzer, Jeffrey
2012-01-01
Microwave and millimeter-wave remote sensing techniques are fast becoming a necessity in many aspects of security as detection and classification of objects or intruders becomes more difficult. This groundbreaking resource offers you expert guidance in this burgeoning area. It provides you with a thorough treatment of the principles of microwave and millimeter-wave remote sensing for security applications, as well as practical coverage of the design of radiometer, radar, and imaging systems. You learn how to design active and passive sensors for intruder detection, concealed object detection,
Microsystem integration from RF to millimeter wave applications
Vähä-Heikkilä, T.; Lahti, M.
2015-05-01
Radio frequency systems have been applied successfully to consumer products. Typically these radios operate up to 6 GHz. During recent years, interest towards microwave (up to 30 GHz) and millimeter wave frequencies (30 ... 300 GHz) has increased significantly. Technologies have been developed to have high performance microwave and millimeter wave components. On the other hand, integration and packaging technologies have not developed as fast while their importance is crucial especially in consumer applications. This presentation focuses to latest trends in wireless microsystem component integration and packaging trends backed up with demonstrators and measured results based on VTT's demonstrations.
Kengne, E; Lakhssassi, A
2015-03-01
We consider a lossless one-dimensional nonlinear discrete bi-inductance electrical transmission line made of N identical unit cells. When lattice effects are considered, we use the reductive perturbation method in the semidiscrete limit to show that the dynamics of modulated waves can be modeled by the classical nonlinear Schrödinger (CNLS) equation, which describes the modulational instability and the propagation of bright and dark solitons on a continuous-wave background. Our theoretical analysis based on the CNLS equation predicts either two or four frequency regions with different behavior concerning the modulational instability of a plane wave. With the help of the analytical solutions of the CNLS equation, we investigate analytically the effects of the linear capacitance CS on the dynamics of matter-wave solitons in the network. Our results reveal that the linear parameter CS can be used to manipulate the motion of bright, dark, and kink soliton in the network.
Statics and dynamics of a self-bound dipolar matter-wave droplet
Adhikari, S. K.
2017-02-01
We study the statics and dynamics of a stable, mobile, self-bound three-dimensional dipolar matter-wave droplet created in the presence of a tiny repulsive three-body interaction. In frontal collision with an impact parameter and in angular collision at large velocities along all directions two droplets behave like quantum solitons. Such a collision is found to be quasi elastic and the droplets emerge undeformed after collision without any change of velocity. However, in a collision at small velocities the axisymmeric dipolar interaction plays a significant role and the collision dynamics is sensitive to the direction of motion. For an encounter along the z direction at small velocities, two droplets, polarized along the z direction, coalesce to form a larger droplet—a droplet molecule. For an encounter along the x direction at small velocities, the same droplets stay apart and never meet each other due to the dipolar repulsion. The present study is based on an analytic variational approximation and a numerical solution of the mean-field Gross–Pitaevskii equation using the parameters of 52Cr atoms.
Gravitational waves as a probe of dark matter mini-spikes
Eda, Kazunari; Kuroyanagi, Sachiko; Silk, Joseph
2014-01-01
Recent studies show that an intermediate mass black hole (IMBH) may develop a dark matter (DM) mini-halo according to some BH formation scenarios. We consider a binary system composed of an IMBH surrounded by a DM mini-spike and a stellar mass object orbiting around the IMBH. The binary evolves due to gravitational pull and dynamical friction from the DM mini-spike and back-reaction from its gravitational wave (GW) radiation which can be detected by future space-borne GW experiments such as eLISA/NGO. We consider a single power-law model for the DM mini-spike which is assumed to consist of non-annihilating DM particles and demonstrate that an eLISA/NGO detection of GW from such a binary enables us to measure the DM mini-spike parameters very accurately. For instance, in our reference case originally advocated by Zhao and Silk (2005) and Bertone et al. (2005), we could determine the power-law index $\\alpha$ of the DM mini-spike radial profile with a 1 $\\sigma$ relative error of $\\pm 5\\times 10^{-6}$ for a GW s...
Constraining warm dark matter mass with cosmic reionization and gravitational wave
Tan, W W; Cheng, K S
2016-01-01
We constrain the warm dark matter (WDM) particle mass with the observations of cosmic reionization and CMB optical depth. We suggest that the GWs from stellar mass black holes (BHs) could give a further constraint on WDM particle mass for future observations. The star formation rates (SFRs) of Population I/II (Pop I/II) and Population III (Pop III) stars are also derived. If the metallicity of the universe have been enriched beyond the critical value of $Z_{\\rm crit}=10^{-3.5}Z_{\\odot}$, the star formation shift from Pop III to Pop I/II stars. Our results show that the SFRs are quite dependent on the WDM particle mass, especially at high redshifts. Combing with the reionization history and CMB optical depth derived from the recent \\emph{Planck} mission, we find that the current data requires the WDM particle mass in a narrow range of $1 < m_x < 3$ keV. Furthermore, we suggest that the stochastic gravitational wave background (SGWB) produced by stellar BHs could give a further constraint on the WDM parti...
Gravitational wave signatures of inflationary models from Primordial Black Hole dark matter
García-Bellido, Juan; Peloso, Marco; Unal, Caner
2017-09-01
Primordial Black Holes (PBH) could be the cold dark matter of the universe. They could have arisen from large (order one) curvature fluctuations produced during inflation that reentered the horizon in the radiation era. At reentry, these fluctuations source gravitational waves (GW) via second order anisotropic stresses. These GW, together with those (possibly) sourced during inflation by the same mechanism responsible for the large curvature fluctuations, constitute a primordial stochastic GW background (SGWB) that unavoidably accompanies the PBH formation. We study how the amplitude and the range of frequencies of this signal depend on the statistics (Gaussian versus χ2) of the primordial curvature fluctuations, and on the evolution of the PBH mass function due to accretion and merging. We then compare this signal with the sensitivity of present and future detectors, at PTA and LISA scales. We find that this SGWB will help to probe, or strongly constrain, the early universe mechanism of PBH production. The comparison between the peak mass of the PBH distribution and the peak frequency of this SGWB will provide important information on the merging and accretion evolution of the PBH mass distribution from their formation to the present era. Different assumptions on the statistics and on the PBH evolution also result in different amounts of CMB μ-distortions. Therefore the above results can be complemented by the detection (or the absence) of μ-distortions with an experiment such as PIXIE.
Application of Ultrasonic Waves on Maintaining Freshness of Tilapia Fillet
Ruddy Suwandi
2015-06-01
Full Text Available ish fillet is one of fisheries products that easily deteriorated; hence handling techniques are needed to maintain the freshness. Ultrasonic wave have been widely applied to some of food products for maintaining freshness through microbial inactivation, however the ultrasonic application to fisheries products has not been reported. The purpose of this study was to analyze the effect of ultrasonic wave on fish freshness. The stages of the study were sample preparation, sonication, freshness parameters examination and histology observation. Ultrasonic wave did not affectthe organoleptic value and the TVB, but affected the pH value and the TPC. The sample in which the TPC value was found significantly different, were further observed after 48 and 96 hours storage. The result showed that the TPC value of sonicated sample for 9 minutes was lower to that of without sonication. Histology analysis showed, however, sonication made the structure of muscle fiber less compact and deformation of myomer was found.
Dikande, Alain Moise; Ebobenow, Joseph
2010-01-01
A theoretical scheme for an experimental implementation involving bisolitonic matter waves from an attractive Bose-Einstein condensate, is considered within the framework of a non-perturbative approach to the associate Gross-Pitaevskii equation. The model consists of a single condensate subjected to an expulsive harmonic potential creating a double-condensate structure, and a gravitational potential that induces atomic exchanges between the two overlapping post condensates. Using a non-isospectral scattering transform method, exact expressions for the bright-matter-wave bisolitons are found in terms of double-lump envelopes with the co-propagating pulses displaying more or less pronounced differences in their widths and tails depending on the mass of atoms composing the condensate.
Song Chang-Sheng; Li Jing; Zong Feng-De
2012-01-01
An extended variation approach to describing the dynamic evolution of self-attractive Bose-Einstein condensates is developed.We consider bright matter-wave solitons in the presence of a parabolic magnetic potential and a timespace periodic optical lattice.The dynamics of condensates is shown to be well approximated by four coupled nonlinear differential equations.A noteworthy feature is that the extended variation approach gives a critical strength ratio to support multiple stable lattice sites for the condensate.We further examine the existence of the solitons and their stabilities at the multiple stable lattice sites. In this case,the analytical predictions of Bose-Einstein condensates variational dynamics are found to be in good agreement with numerical simulations.We then find a stable region for successful manipulating matter-wave solitons without collapse,which are dragged from an initial stationary to a prescribed position by a moving periodic optical lattice.
Planar millimeter wave radar frontend for automotive applications
2003-01-01
A fully integrated planar sensor for 77 GHz automotive applications is presented. The frontend consists of a transceiver multichip module and an electronically steerable microstrip patch array. The antenna feed network is based on a modified Rotman-lens and connected to the array in a multilayer approach offering higher integration. Furthermore, the frontend comprises a phase lock loop to allow proper frequency-modulated continuous wave (FMCW) radar operation. The latest experimental results ...
Lush, David C
2016-01-01
It is investigated whether the Planck-Einstein relation between the energy and frequency of light quanta, and the de Broglie wavelength of matter can be wholly or partially explained as consequences of the relativistic Doppler shift of electromagnetic fields caused by oscillating electric dipoles within the elementary particles constituting light and matter, and their electromagnetic interaction with similarly constituted particles. Assuming the oscillation is at the zitterbewegung frequency of the Dirac electron theory, the photon energy is found to be approximately half the value expected according to the Planck-Einstein relation. The relativistically Doppler shifted time-symmetric electromagnetic field due to the particle is found to have a superluminal phase velocity equal to that of the de Broglie matter wave, a group velocity equal to the particle velocity, and a wavelength of \\(h/p\\).
VERA M. FERNANDES-DE-LIMA
2001-09-01
Full Text Available The brain is an excitable media in which excitation waves propagate at several scales of time and space. ''One-dimensional'' action potentials (millisecond scale along the axon membrane, and spreading depression waves (seconds to minutes at the three dimensions of the gray matter neuropil (complex of interacting membranes are examples of excitation waves. In the retina, excitation waves have a prominent intrinsic optical signal (IOS. This optical signal is created by light scatter and has different components at the red and blue end of the spectrum. We could observe the wave onset in the retina, and measure the optical changes at the critical transition from quiescence to propagating wave. The results demonstrated the presence of fluctuations preceding propagation and suggested a phase transition. We have interpreted these results based on an extrapolation from Tasaki's experiments with action potentials and volume phase transitions of polymers. Thus, the scatter of red light appeared to be a volume phase transition in the extracellular matrix that was caused by the interactions between the cellular membrane cell coat and the extracellular sugar and protein complexes. If this hypothesis were correct, then forcing extracellular current flow should create a similar signal in another tissue, provided that this tissue was also transparent to light and with a similarly narrow extracellular space. This control tissue exists and it is the crystalline lens. We performed the experiments and confirmed the optical changes. Phase transitions in the extracellular polymers could be an important part of the long-range correlations found during wave propagation in central nervous tissue.O encéfalo é um meio excitável no qual ondas de excitação se propagam em várias escalas de tempo e espaço. Potenciais de axônios ''unidimensionais'' (escala de milisegundos ao longo da membrana axonal e ondas de depressão alastrante (segundos a minutos nas três dimens
Neate, Andrew; Truman, Aubrey
2016-05-01
Little is known about dark matter particles save that their most important interactions with ordinary matter are gravitational and that, if they exist, they are stable, slow moving and relatively massive. Based on these assumptions, a semiclassical approximation to the Schrödinger equation under the action of a Coulomb potential should be relevant for modelling their behaviour. We investigate the semiclassical limit of the Schrödinger equation for a particle of mass M under a Coulomb potential in the context of Nelson's stochastic mechanics. This is done using a Freidlin-Wentzell asymptotic series expansion in the parameter ɛ = √{ ħ / M } for the Nelson diffusion. It is shown that for wave functions ψ ˜ exp((R + iS)/ɛ2) where R and S are real valued, the ɛ = 0 behaviour is governed by a constrained Hamiltonian system with Hamiltonian Hr and constraint Hi = 0 where the superscripts r and i denote the real and imaginary parts of the Bohr correspondence limit of the quantum mechanical Hamiltonian, independent of Nelson's ideas. Nelson's stochastic mechanics is restored in dealing with the nodal surface singularities and by computing (correct to first order in ɛ) the relevant diffusion process in terms of Jacobi fields thereby revealing Kepler's laws in a new light. The key here is that the constrained Hamiltonian system has just two solutions corresponding to the forward and backward drifts in Nelson's stochastic mechanics. We discuss the application of this theory to modelling dark matter particles under the influence of a large gravitating point mass.
QMD application of sub-saturated nuclear matter
Maruyama, Toshiki; Maruyama, Tomoyuki; Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Niita, Koji; Chikamatsu, Kazuhiro
1997-05-01
QMD (quantum molecular dynamics) has not been applied to supernova and neutron star matter. We begun to apply QMD, microscopic simulation of nuclear reaction, to the infinite system of nuclear matter. The infinite system was simulated by N particles system under the periodic boundary condition. Pauli potential introduced repulsive force which the same kinds of particles could not approach at phase space, instead of antisymmetrization of the system. Supernova matter was appropriate to the symmetric nuclear matter, the inhomogeneous structure was observed less than 0.8 {rho}{sub 0} of density, but homogeneous more than it. Each nucleus was seen to separate from others less than 0.2 {rho}{sub 0}. Neutron star matter attains {beta} equilibrium and not symmetric matter and the lowest energy was obtained at about 0.03-0.08 of proton content. (S.Y.)
Geiger, R; Bertoldi, A; Canuel, B; Chaibi, W; Danquigny, C; Dutta, I; Fang, B; Gaffet, S; Gillot, J; Holleville, D; Landragin, A; Merzougui, M; Riou, I; Savoie, D; Bouyer, P
2015-01-01
The MIGA project aims at demonstrating precision measurements of gravity with cold atom sensors in a large scale instrument and at studying the associated powerful applications in geosciences and fundamental physics. The firt stage of the project (2013-2018) will consist in building a 300-meter long optical cavity to interrogate atom interferometers and will be based at the low noise underground laboratory LSBB based in Rustrel, France. The second stage of the project (2018-2023) will be dedicated to science runs and data analyses in order to probe the spatio-temporal structure of the local gravity field of the LSBB region, which represents a generic site of hydrological interest. MIGA will also assess future potential applications of atom interferometry to gravitational wave detection in the frequency band 0.1-10 Hz hardly covered by future long baseline optical interferometers. This paper presents the main objectives of the project, the status of the construction of the instrument and the motivation for the...
High-Temperature Piezoelectric Crystals for Acoustic Wave Sensor Applications.
Zu, Hongfei; Wu, Huiyan; Wang, Qing-Ming
2016-03-01
In this review paper, nine different types of high-temperature piezoelectric crystals and their sensor applications are overviewed. The important materials' properties of these piezoelectric crystals including dielectric constant, elastic coefficients, piezoelectric coefficients, electromechanical coupling coefficients, and mechanical quality factor are discussed in detail. The determination methods of these physical properties are also presented. Moreover, the growth methods, structures, and properties of these piezoelectric crystals are summarized and compared. Of particular interest are langasite and oxyborate crystals, which exhibit no phase transitions prior to their melting points ∼ 1500 °C and possess high electrical resistivity, piezoelectric coefficients, and mechanical quality factor at ultrahigh temperature ( ∼ 1000 °C). Finally, some research results on surface acoustic wave (SAW) and bulk acoustic wave (BAW) sensors developed using this high-temperature piezoelectric crystals are discussed.
Collective transport for active matter run-and-tumble disk systems on a traveling-wave substrate
Sándor, Cs.; Libál, A.; Reichhardt, C.; Reichhardt, C. J. Olson
2017-01-01
We examine numerically the transport of an assembly of active run-and-tumble disks interacting with a traveling-wave substrate. We show that as a function of substrate strength, wave speed, disk activity, and disk density, a variety of dynamical phases arise that are correlated with the structure and net flux of disks. We find that there is a sharp transition into a state in which the disks are only partially coupled to the substrate and form a phase-separated cluster state. This transition is associated with a drop in the net disk flux, and it can occur as a function of the substrate speed, maximum substrate force, disk run time, and disk density. Since variation of the disk activity parameters produces different disk drift rates for a fixed traveling-wave speed on the substrate, the system we consider could be used as an efficient method for active matter species separation. Within the cluster phase, we find that in some regimes the motion of the cluster center of mass is in the opposite direction to that of the traveling wave, while when the maximum substrate force is increased, the cluster drifts in the direction of the traveling wave. This suggests that swarming or clustering motion can serve as a method by which an active system can collectively move against an external drift.
Constraining Warm Dark Matter Mass with Cosmic Reionization and Gravitational Waves
Tan, Wei-Wei; Wang, F. Y.; Cheng, K. S.
2016-09-01
We constrain the warm dark matter (WDM) particle mass with observations of cosmic reionization and CMB optical depth. We suggest that the gravitational waves (GWs) from stellar-mass black holes (BHs) could give a further constraint on WDM particle mass for future observations. The star formation rates (SFRs) of Population I/II (Pop I/II) and Population III (Pop III) stars are also derived. If the metallicity of the universe is enriched beyond the critical value of {Z}{{crit}}={10}-3.5 {Z}⊙ , the star formation shifts from Pop III to Pop I/II stars. Our results show that the SFRs are quite dependent on the WDM particle mass, especially at high redshifts. Combined with the reionization history and CMB optical depth derived from the recent Planck mission, we find that the current data require the WDM particle mass to be in a narrow range of 1 {{keV}}≲ {m}{{x}}≲ 3 {{keV}}. Furthermore, we suggest that the stochastic gravitational wave background (SGWB) produced by stellar BHs could give a further constraint on the WDM particle mass for future observations. For {m}{{x}}=3 {{keV}}, with Salpeter (Chabrier) initial mass function (IMF), the SGWB from Pop I/II BHs has a peak amplitude of {{{Ω }}}{{GW}}≈ 2.8× {10}-9 (5.0× {10}-9) at f=316{{Hz}}, while the GW radiation at f\\lt 10 Hz is seriously suppressed. For {m}{{x}}=1 {{keV}}, the SGWB peak amplitude is the same as that for {m}{{x}}=1 {{keV}}, but a little lower at low frequencies. Therefore, it is hard to constrain the WDM particle mass by the SGWB from Pop I/II BHs. To assess the detectability of the GW signal, we also calculate the signal-to-noise ratios (S/N), which are {{S}}/{{N}}=37.7 (66.5) and 27 (47.7) for {m}{{x}}=3 {{keV}} and {m}{{x}}=1 {{keV}} for the Einstein Telescope with Salpeter (Chabrier) IMF, respectively. The SGWB from Pop III BHs is very dependent on the WDM particle mass, the GW strength could be an order of magnitude different, and the frequency band could be two times different for {m
Electromagnetic Lead Screw for Potential Wave Energy Application
Lu, Kaiyuan; Wu, Weimin
2014-01-01
This paper presents a new type electromagnetic lead screw (EMLS) intended for wave energy application. Similar to the mechanical lead screw, this electromagnetic version can transfer slow linear motion to high-rotational motion, offering gearing effects. Compared with the existing pure magnetic...... lead screw (MLS) employing permanent magnets only, the new EMLS proposed uses dc current to provide the required helical-shape magnetic field, offering a much simpler, robust structure compared with the MLS. The working principle and the performances of this EMLS are analyzed in this paper. Comparison...
Controllable azimuthons of four-wave mixing and their applications
Wang, R. M.; Che, J. L.; Wang, X. P.; Lan, H. Y.; Wu, Z. K.; Zhang, Y. Q.; Zhang, Y. P.
2014-08-01
We report controllable azimuthons of four-wave mixing (FWM), which can be modulated by several parameters in experiment. The spot number, splitting depth, rotation angular velocity and direction of such azimuthons can be controlled by the frequency and intensity of the FWM signal or the dressing field through the cross-phase modulation due to atomic coherence. The intensity gain of the azimuthons can be modulated by frequency detuning through quantum parametric amplification. The quantum correlated FWM vortex is observed in experiment. We also discuss the applications of such controllable azimuthons in all-optical circulators, multiplexers (demultiplexers), routers, cross-connects and optical amplifiers.
Effective equations for matter-wave gap solitons in higher-order transversal states.
Mateo, A Muñoz; Delgado, V
2013-10-01
We demonstrate that an important class of nonlinear stationary solutions of the three-dimensional (3D) Gross-Pitaevskii equation (GPE) exhibiting nontrivial transversal configurations can be found and characterized in terms of an effective one-dimensional (1D) model. Using a variational approach we derive effective equations of lower dimensionality for BECs in (m,n(r)) transversal states (states featuring a central vortex of charge m as well as n(r) concentric zero-density rings at every z plane) which provides us with a good approximate solution of the original 3D problem. Since the specifics of the transversal dynamics can be absorbed in the renormalization of a couple of parameters, the functional form of the equations obtained is universal. The model proposed finds its principal application in the study of the existence and classification of 3D gap solitons supported by 1D optical lattices, where in addition to providing a good estimate for the 3D wave functions it is able to make very good predictions for the μ(N) curves characterizing the different fundamental families. We have corroborated the validity of our model by comparing its predictions with those from the exact numerical solution of the full 3D GPE.
48 CFR 52.227-10 - Filing of Patent Applications-Classified Subject Matter.
2010-10-01
... Applications-Classified Subject Matter. 52.227-10 Section 52.227-10 Federal Acquisition Regulations System... Text of Provisions and Clauses 52.227-10 Filing of Patent Applications—Classified Subject Matter. As prescribed at 27.203-2, insert the following clause: Filing of Patent Applications—Classified Subject...
Unlocking the full potential of wave-matter nonlinear coupling in the epsilon-near-zero regime
Ciattoni, Alessandro; Marini, Andrea; Di Falco, Andrea; Faccio, Daniele; Scalora, Michael
2015-01-01
In recent years, unconventional metamaterial properties have triggered a revolution of electromagnetic research which has unveiled novel scenarios of wave-matter interaction. A very small dielectric permittivity is a leading example of such unusual features, since it produces an exotic static-like regime where the electromagnetic field is spatially slowly-varying over a physically large region. The so-called epsilon-near-zero metamaterials thus offer an ideal platform where to manipulate the inner details of the "stretched" field. Here we theoretically prove that a standard nonlinearity is able to operate such a manipulation to the point that even a thin slab produces a dramatic nonlinear pulse transformation, if the dielectric permittivity is very small within the field bandwidth. The predicted non-resonant releasing of full nonlinear coupling produced by the epsilon-near-zero condition does not resort to any field enhancement mechanisms and opens novel routes to exploiting matter nonlinearity for steering t...
Su, Shih-Wei; Lu, Zhen-Kai; Gou, Shih-Chuan; Liao, Wen-Te
2016-10-01
Cavity quantum electrodynamics (CQED) has played a central role in demonstrating the fundamental principles of the quantum world, and in particular those of atom-light interactions. Developing fast, dynamical and non-mechanical control over a CQED system is particularly desirable for controlling atomic dynamics and building future quantum networks at high speed. However conventional mirrors do not allow for such flexible and fast controls over their coupling to intracavity atoms mediated by photons. Here we theoretically investigate a novel all-optical CQED system composed of a binary Bose-Einstein condensate (BEC) sandwiched by two atomic ensembles. The highly tunable atomic dispersion of the CQED system enables the medium to act as a versatile, all-optically controlled atomic mirror that can be employed to manipulate the vacuum-induced diffraction of matter-wave superradiance. Our study illustrates a innovative all-optical element of atomtroics and sheds new light on controlling light-matter interactions.
Mesoscopics of ultrasound and seismic waves: application to passive imaging
Larose, É.
2006-05-01
This manuscript deals with different aspects of the propagation of acoustic and seismic waves in heterogeneous media, both simply and multiply scattering ones. After a short introduction on conventional imaging techniques, we describe two observations that demonstrate the presence of multiple scattering in seismic records: the equipartition principle, and the coherent backscattering effect (Chap. 2). Multiple scattering is related to the mesoscopic nature of seismic and acoustic waves, and is a strong limitation for conventional techniques like medical or seismic imaging. In the following part of the manuscript (Chaps. 3 5), we present an application of mesoscopic physics to acoustic and seismic waves: the principle of passive imaging. By correlating records of ambient noise or diffuse waves obtained at two passive sensors, it is possible to reconstruct the impulse response of the medium as if a source was placed at one sensor. This provides the opportunity of doing acoustics and seismology without a source. Several aspects of this technique are presented here, starting with theoretical considerations and numerical simulations (Chaps. 3, 4). Then we present experimental applications (Chap. 5) to ultrasound (passive tomography of a layered medium) and to seismic waves (passive imaging of California, and the Moon, with micro-seismic noise). Physique mésoscopique des ultrasons et des ondes sismiques : application à l'imagerie passive. Cet article de revue rassemble plusieurs aspects fondamentaux et appliqués de la propagation des ondes acoustiques et élastiques dans les milieux hétérogènes, en régime de diffusion simple ou multiple. Après une introduction sur les techniques conventionelles d'imagerie sismique et ultrasonore, nous présentons deux expériences qui mettent en évidence la présence de diffusion multiple dans les enregistrements sismologiques : l'équipartition des ondes, et la rétrodiffusion cohérente (Chap. 2). La diffusion multiple des
宣恒农; 左苗
2011-01-01
We present three families of exact matter-wave soliton solutions for an effective one-dimension two- component Bose-Einstein condensates （BECs） with tunable interactions, harmonic potential and gain or loss term. We investigate the dynamics of bright-bright solitons, bright-dark solitons and dark-dark solitons for the time-dependent expulsive harmonic trap potential, periodically modulated harmonic trap potential, and kinklike modulated harmonic trap potential. Through the Feshbach resonance, these dynamics can be realized in experiments by suitable control of time-dependent trap parameters, atomic interactions, and interaction with thermal cloud.
Dynamics and Matter-Wave Solitons in Bose-Einstein Condensates with Two- and Three-Body Interactions
Jing Chen
2014-01-01
Full Text Available By means of similarity transformation, this paper proposes the matter-wave soliton solutions and dynamics of the variable coefficient cubic-quintic nonlinear Schrödinger equation arising from Bose-Einstein condensates with time-dependent two- and three-body interactions. It is found that, under the effect of time-dependent two- and three-body interaction and harmonic potential with time-dependent frequency, the density of atom condensates will gradually diminish and finally collapse.
Integrated horn antennas for millimeter-wave applications
Rebeiz, Gabriel M.; Katehi, Linda P. B.; Ali-Ahmad, Walid Y.; Eleftheriades, George V.; Ling, Curtis C.
1992-02-01
The development of integrated horn antennas since their introduction in 1987 is reviewed. The integrated horn is fabricated by suspending a dipole antenna, on a thin dielectric membrane, in a pyramidal cavity etched in silicon. Recent progress has resulted in optimized low- and high-gain designs, with single and double polarization for remote-sensing and communication applications. A full-wave analysis technique has resulted in an integrated antenna with performance comparable to that of waveguide-fed corrugated-horn antennas. The integrated horn design can be extended to large arrays, for imaging and phased-array applications, while leaving plenty of room for the RF and IF processing circuitry. Theoretical and experimental results at microwave frequencies and at 90 GHz, 240 GHz, and 802 GHz are presented.
The pump-probe coupling of matter wave packets to remote lattice states
Sherson, Jacob F; Park, Sung Jong; Pedersen, Poul Lindholm;
2012-01-01
containing a Bose–Einstein condensate. The evolution of these wave packets is monitored in situ and their six-photon reflection at a band gap is observed. In direct analogy with pump–probe spectroscopy, a probe pulse allows for the resonant de-excitation of the wave packet into states localized around...
Fornaro, L
2000-01-01
When the ionizing radiation interact with the matter different effects happen on the radiations and on the matter. Many of these effects have been used with very different ends giving place to applications in several fields, among those that stand out the applications in medicine and industry. Basically, two different dispositions exist: one in that the radiation crosses or retrodisperse in the material and another in that the radiation acts on and it modifies the material.
Applications of the wave kinetic approach: from laser wakefields to drift wave turbulence
Trines, R. M. G. M.; Bingham, R.; Silva, L. O.; Mendonça, J. T.; Shukla, P. K.; Murphy, C. D.; Dunlop, M. W.; Davies, J. A.; Bamford, R.; Vaivads, A.; Norreys, P. A.
2010-12-01
Nonlinear wave-driven processes in plasmas are normally described by either a monochromatic pump wave that couples to other monochromatic waves, or as a random phase wave coupling to other random phase waves. An alternative approach involves a random or broadband pump coupling to monochromatic and/or coherent structures in the plasma. This approach can be implemented through the wave-kinetic model. In this model, the incoming pump wave is described by either a bunch (for coherent waves) or a sea (for random phase waves) of quasi-particles. This approach has been applied to both photon acceleration in laser wakefields and drift wave turbulence in magnetized plasma edge configurations. Numerical simulations have been compared to experiments, varying from photon acceleration to drift mode-zonal flow turbulence, and good qualitative correspondences have been found in all cases.
Eda, Kazunari; Kuroyanagi, Sachiko; Silk, Joseph
2013-01-01
An intermediate mass black hole (IMBH) may have a dark matter (DM) mini-halo around it and develop a spiky structure within less than a parsec from the IMBH. When a stellar mass object is captured by the mini-halo, it eventually infalls into such an IMBH due to gravitational wave back reaction which in turn could be observed directly by future space-borne gravitational wave experiments such as eLISA/NGO. In this paper, we show that the GW detectability strongly depends on the radial profile of the DM distribution. So if the GW is detected, the power index, that is, the DM density distribution would be determined very accurately. The DM density distribution obtained would make it clear how the IMBH has evolved from a seed BH and whether the IMBH has experienced major mergers in the past. Unlike the gamma ray observations of DM annihilation, GW is just sensitive to the radial profile of the DM distribution and even to non-interacting DM. Hence the effect we demonstrate here can be used as a new and powerful pro...
Atanackovic, Teodor M; Stankovic, Bogoljub; Zorica, Du?an
2014-01-01
The books Fractional Calculus with Applications in Mechanics: Vibrations and Diffusion Processes and Fractional Calculus with Applications in Mechanics: Wave Propagation, Impact and Variational Principles contain various applications of fractional calculus to the fields of classical mechanics. Namely, the books study problems in fields such as viscoelasticity of fractional order, lateral vibrations of a rod of fractional order type, lateral vibrations of a rod positioned on fractional order viscoelastic foundations, diffusion-wave phenomena, heat conduction, wave propagation, forced oscillati
Kinoshita, T.; Sato, K.
2012-12-01
The Transformed Eulerian-Mean (TEM) equations formulated by Andrews and McIntyre (1976, 1978) has been widely used to examine wave-mean flow interaction in the meridional cross section. Although a lot of efforts have been made to generalize the TEM equations to three dimensions so far, formulae derived by previous studies are applicable to particular waves, mainly Rossby waves on the quasi-geostrophic (QG) equations or inertia-gravity waves on the primitive equations. This study has newly formulated three-dimensional (3D) TEM equations which are applicable to both Rossby waves and gravity waves. The formulae can be used to examine the 3D material transport driven by these waves. Moreover, two kinds of 3D wave activity flux have been derived respectively for describing the wave force to the mean flow and for the wave propagation. The residual mean flow is expressed with the sum of the Eulerian-mean flow and the Stokes drift in the 2D TEM equations. Thus, a formulation is made for the 3D Stokes drift on the primitive equation (PRSD) from its original definition using a small amplitude theory for a slowly-varying mean flow. The PRSD is equivalent to the 3D Stokes drift derived by Kinoshita et al. (2010) for gravity waves for the constant Coriolis parameter and to the 3D QG Stokes drift which is also derived in this study for the small Rossby number limit. The 3D wave activity flux (3D-flux-M), whose divergence corresponds to the wave force, is derived by using PRSD. The 3D residual mean flow associated with synoptic-scale wave disturbances in the upper troposphere in April is investigated by applying the new formulae to ERA-Interim data. It is found that the sum of time-mean unbalanced flow and PRSD is southward in the east end of the storm track although it is northward in the west as is consistent with the 2D residual flow. A case study is also made for dominant gravity waves around the Southern Andes by applying the PRSD and 3D-flux-M to the simulation data of a
2008-01-01
Three-component seismic exploration through P-wave source and three-component geophone is an effective technique used in complicated reservoir exploration. In three-component seismic exploration data processing,one of the difficulties is static correction of converted wave. This paper analyzes propagation characteristics of non-converted and converted refracted waves,and discovers a favor-able condition for the formation of converted refracted wave,i.e. the velocity of overlaying medium S wave is much lower than that of underlying medium S wave. In addition,the paper proposes the static correction method of converted wave based on PPS converted refracted wave,and processes the real three-component seismic data with better results of static correction of converted wave.
Excitation energy transfer processes in condensed matter theory and applications
Singh, Jai
1994-01-01
Applying a unified quantum approach, contributors offer fresh insights into the theoretical developments in the excitation energy transfer processes in condensed matter This comprehensive volume examines Frenkel and Wannier excitonic processes; rates of excitonic processes; theory of laser sputter and polymer ablation; and polarons, excitonic polarons and self-trapping
Organic Matter Application Can Reduce Copper Toxicity in Tomato Plants
Campbell, Brian
2010-01-01
Copper fungicides and bactericides are often used in tomato cultivation and can cause toxic Cu levels in soils. In order to combat this, organic matter can be applied to induce chelation reactions and form a soluble complex by which much of the Cu can leach out of the soil profile or be taken up safely by plants. Organic acids such as citric,…
Organic Matter Application Can Reduce Copper Toxicity in Tomato Plants
Campbell, Brian
2010-01-01
Copper fungicides and bactericides are often used in tomato cultivation and can cause toxic Cu levels in soils. In order to combat this, organic matter can be applied to induce chelation reactions and form a soluble complex by which much of the Cu can leach out of the soil profile or be taken up safely by plants. Organic acids such as citric,…
Schive, Hsi-Yu; Broadhurst, Tom; Huang, Kuan-Wei
2015-01-01
The newly established luminosity functions of high-z galaxies at $4 \\lesssim z \\lesssim 10$ can provide a stringent check on dark matter models that aim to explain the core properties of dwarf galaxies. The cores of dwarf spheroidal galaxies are understood to be too large to be accounted for by free streaming of warm dark matter without overly suppressing the formation of such galaxies. Here we demonstrate with cosmological simulations that wave dark matter, $\\psi$DM, appropriate for light bosons such as axions, does not suffer this problem, given a boson mass of $m_{\\psi} \\ge 1.2 \\times 10^{-22}{\\,\\rm eV}$ ($2\\sigma$). In this case, the halo mass function is suppressed below $\\sim 10^{10}{\\,M_\\odot}$ at a level that is consistent with the high-z luminosity functions, while simultaneously generating the kpc-scale cores in dwarf galaxies arising from the solitonic ground state in $\\psi$DM. We demonstrate that the reionization history in this scenario is consistent with the Thomson optical depth recently report...
Ion streaming instabilities with application to collisionless shock wave structure
Golden, K. I.; Linson, L. M.; Mani, S. A.
1973-01-01
The electromagnetic dispersion relation for two counterstreaming ion beams of arbitrary relative strength flowing parallel to a dc magnetic field is derived. The beams flow through a stationary electron background and the dispersion relation in the fluid approximation is unaffected by the electron thermal pressure. Magnetic effects on the ion beams are included, but the electrons are treated as a magnetized fluid. The dispersion relation is solved with a zero net current condition applied and the regions of instability in the k-U space (U is the relative velocity between the two ion beams) are presented. These results are extensions of Kovner's analysis for weak beams. The parameters are then chosen to be applicable for parallel shocks. It is found that unstable waves with zero group velocity in the shock frame can exist near the leading edge of the shock for upstream Alfven Mach numbers greater than 5.5.
Goos-Hänchen-like shift of three-level matter wave incident on Raman beams
Duan, Zhenglu; Hu, Liyun; Xu, XueXiang; Liu, Cunjin
2014-07-01
When a three-level atomic wavepacket is obliquely incident on a "edium slab" consisting of two far-detuned laser beams, there exists lateral shift between reflection and incident points at the surface of a "medium slab", analogous to optical Goos-Hanchen effect. We evaluate lateral shifts for reflected and transmitted waves via expansion of reflection and transmission coefficients, in contrast to the stationary phase method. Results show that lateral shifts can be either positive or negative dependent on the incident angle and the atomic internal state. Interestingly, a giant lateral shift of transmitted wave with high transmission probability is observed, which is helpful to observe such lateral shifts experimentally. Different from the two-level atomic wave case, we find that quantum interference between different atomic states plays crucial role on the transmission intensity and corresponding lateral shifts.
INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Subsonic radiation waves in neon
Loseva, T. V.; Nemchinov, I. V.
1989-02-01
Numerical methods are used to investigate the propagation of plane subsonic radiation waves in neon from an obstacle in the direction opposite to the incident radiation of Nd and CO2 lasers. An analysis is made of the influence of the power density of the incident radiation (in the range 10-100 MW/cm2) and of the initial density of neon (beginning from the normal valuep ρ0 up to 10ρ0) on the various characteristics of subsonic radiation waves. It is shown that waves traveling in neon can provide an effective source of radiation with a continuous spectrum and an efficiency of ~ 12-27% in the ultraviolet range (with a characteristic photon energy ~ 5-10 eV).
High frequency surface acoustic wave resonator-based sensor for particulate matter detection
Thomas, Sanju; Cole, Marina; Villa-López, Farah Helue; Gardner, J. W.
2016-01-01
This paper describes the characterization of high frequency Surface Acoustic Wave Resonator-based (SAWR) sensors, for the detection of micron and sub-micron sized particles. The sensor comprises two 262 MHz ST-cut quartz based Rayleigh wave SAWRs where one is used for particle detection and the other as a reference. Electro-acoustic detection of different sized particles shows a strong relationship between mass sensitivity (Δf/Δm) and particle diameter (Dp). This enables frequency-dependent S...
Ultrasonic spectroscopy applications in condensed matter physics and materials science
Leisure, Robert G
2017-01-01
Ultrasonic spectroscopy is a technique widely used in solid-state physics, materials science, and geology that utilizes acoustic waves to determine fundamental physical properties of materials, such as their elasticity and mechanical energy dissipation. This book provides complete coverage of the main issues relevant to the design, analysis, and interpretation of ultrasonic experiments. Topics including elasticity, acoustic waves in solids, ultrasonic loss, and the relation of elastic constants to thermodynamic potentials are covered in depth. Modern techniques and experimental methods including resonant ultrasound spectroscopy, digital pulse-echo, and picosecond ultrasound are also introduced and reviewed. This self-contained book includes extensive background theory and is accessible to students new to the field of ultrasonic spectroscopy, as well as to graduate students and researchers in physics, engineering, materials science, and geophysics.
Decay of Langmuir wave in dense plasmas and warm dense matter
Son, S; Moon, Sung Joon
2010-01-01
The decays of the Langmuir waves in dense plasmas are computed using the dielectric function theory widely used in the solid state physics. Four cases are considered: a classical plasma, a Maxwellian plasma, a degenerate quantum plasma, and a partially degenerate plasma. The result is considerably different from the conventional Landau damping theory.
Snelder, Marieke
2015-01-01
The main focus of this thesis is to understand the correlations present at the s-wave/three-dimensional topological insulator interface both theoretically and experimentally. In the future, devices containing these kind of interfaces can be used to create and manipulate a Majorana zero-energy mode w
Clinical application of shock wave therapy (SWT) in musculoskeletal disorders.
Ioppolo, F; Rompe, J D; Furia, J P; Cacchio, A
2014-04-01
Currently the application of shock wave therapy (SWT) in musculoskeletal disorders has been primarily used in the treatment of tendinopathies (proximal plantar fasciopathy, lateral elbow tendinopathy, calcific tendinopathy of the shoulder, and patellar tendinopathy, etc.) and bone defects (delayed- and non-union of bone fractures, avascular necrosis of femoral head, etc.). Although the mechanism of their therapeutic effects are still unknown, the majority of published papers have shown positive and beneficial effects of using SWT as a treatment for musculoskeletal disorders, with a success rate ranging from 65% to 91%, while the complications are low or negligible. The purpose of this paper is to inform the reader about the published data on the clinical application of SWT in the treatment of musculoskeletal disorders. In this paper, with the help of a literature review, indications and success rates for SWT in the treatment of musculoskeletal disorders are outlined, while adequate SWT parameters (e.g., rate of impulses, energy flux density, etc.) are defined according to the present state of knowledge.
On abelianizations of the ABJM model and applications to condensed matter
Murugan, Jeff, E-mail: jeff@nassp.uct.ac.za [The Laboratory for Quantum Gravity and Strings, Department of Mathematics and Applied Mathematics, University of Cape Town (South Africa); Nastase, Horatiu, E-mail: nastase@ift.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Sao Paulo, SP (Brazil). Instituto de Fisica Teorica
2015-08-15
In applications of AdS/CFT to condensed matter systems in 2+1 dimensions, the ABJM model is often used; however, the condensed matter models are usually abelian and contain charged fields. We show that a naive reduction of the ABJM model to N = 1 does not have the desired features, but we can find an abelian reduction that has most features, and we can also add fundamental fields to the ABJM model to obtain other models with similar properties. (author)
Light-Matter Interaction, 1 Fundamentals and Applications
Weiner, John
2003-01-01
A thorough introduction to atomic, molecular, and optical (AMO) science and engineering. Atomic, molecular, and optical (AMO) science and engineering stands at the confluence of strong scientific and technological currents in physics, chemistry, and electrical engineering. It seeks ways to expand our ability to use light for many purposes: to observe and manipulate matter at the atomic scale, to use nanostructures to manipulate light at the subwavelength scale, to develop quantum devices, and to control internal molecular motion and modify chemical reactivity with light. The two-volume Light-M
Graphene-based waveguide resonators for submillimeter-wave applications
Ilić, Andjelija Ž.; Bukvić, Branko; Ilić, Milan M.; Budimir, Djuradj
2016-08-01
Utilization of graphene covered waveguide inserts to form tunable waveguide resonators is theoretically explained and rigorously investigated by means of full-wave numerical electromagnetic simulations. Instead of using graphene-based switching elements, the concept we propose incorporates graphene sheets as parts of a resonator. Electrostatic tuning of the graphene surface conductivity leads to changes in the electromagnetic field boundary conditions at the resonator edges and surfaces, thus producing an effect similar to varying the electrical length of a resonator. The presented outline of the theoretical background serves to give phenomenological insight into the resonator behavior, but it can also be used to develop customized software tools for design and optimization of graphene-based resonators and filters. Due to the linear dependence of the imaginary part of the graphene surface impedance on frequency, the proposed concept was expected to become effective for frequencies above 100 GHz, which is confirmed by the numerical simulations. A frequency range from 100 GHz up to 1100 GHz, where the rectangular waveguides are used, is considered. Simple, all-graphene-based resonators are analyzed first, to assess the achievable tunability and to check the performance throughout the considered frequency range. Graphene-metal combined waveguide resonators are proposed in order to preserve the excellent quality factors typical for the type of waveguide discontinuities used. Dependence of resonator properties on key design parameters is studied in detail. Dependence of resonator properties throughout the frequency range of interest is studied using eight different waveguide sections appropriate for different frequency intervals. Proposed resonators are aimed at applications in the submillimeter-wave spectral region, serving as the compact tunable components for the design of bandpass filters and other devices.
Application of CFD based wave loads in aeroelastic calculations
Schløer, Signe; Paulsen, Bo Terp; Bredmose, Henrik
2014-01-01
realizations compare well with corresponding surface elevations from laboratory experiments. In aeroelastic calculations of an offshore wind turbine on a monopile foundation the hydrodynamic loads due to the potential flow solver and Morison’s equation and the hydrodynamic loads calculated by the coupled......Two fully nonlinear irregular wave realizations with different significant wave heights are considered. The wave realizations are both calculated in the potential flow solver Ocean-Wave3D and in a coupled domain decomposed potential-flow CFD solver. The surface elevations of the calculated wave...
Understanding the core-halo relation of quantum wave dark matter from 3D simulations.
Schive, Hsi-Yu; Liao, Ming-Hsuan; Woo, Tak-Pong; Wong, Shing-Kwong; Chiueh, Tzihong; Broadhurst, Tom; Hwang, W-Y Pauchy
2014-12-31
We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter, described by the Schrödinger-Poisson (SP) equation with a particle mass ∼10(-22) eV. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass (Mc) and halo mass (Mh), Mc∝a(-1/2)Mh(1/3), where a is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of a statistical sample of virialized halos that form in our 3D cosmological simulations and by (ii) merging multiple solitons to create individual virialized objects. Sufficient simulation resolution is achieved by adaptive mesh refinement and graphic processing units acceleration. From this scaling relation, present dwarf satellite galaxies are predicted to have kiloparsec-sized cores and a minimum mass of ∼10(8)M⊙, capable of solving the small-scale controversies in the cold dark matter model. Moreover, galaxies of 2×10(12)M⊙ at z=8 should have massive solitonic cores of ∼2×10(9)M⊙ within ∼60 pc. Such cores can provide a favorable local environment for funneling the gas that leads to the prompt formation of early stellar spheroids and quasars.
Chala, Mikael; Sobolev, Ivan
2016-01-01
A minimal extension of the Standard Model that provides both a dark matter candidate and a strong first-order electroweak phase transition (EWPT) consists of two additional Lorentz and gauge singlets. In this paper we work out a composite Higgs version of this scenario, based on the coset $SO(7)/SO(6)$. We show that by embedding the elementary fermions in appropriate representations of $SO(7)$, all dominant interactions are described by only three free effective parameters. Within the model dependencies of the embedding, the theory predicts one of the singlets to be stable and responsible for the observed dark matter abundance. At the same time, the second singlet introduces new $CP$-violation phases and triggers a strong first-order EWPT, making electroweak baryogenesis feasible. It turns out that this scenario does not conflict with current observations and it is promising for solving the dark matter and baryon asymmetry puzzles. The tight predictions of the model will be accessible at the forthcoming dark ...
Denkmayr, Tobias; Geppert, Hermann; Lemmel, Hartmut; Waegell, Mordecai; Dressel, Justin; Hasegawa, Yuji; Sponar, Stephan
2017-01-01
A method was recently proposed and experimentally realized for characterizing a quantum state by directly measuring its complex probability amplitudes in a particular basis using so-called weak values. Recently, Vallone and Dequal [Phys. Rev. Lett. 116, 040502 (2016), 10.1103/PhysRevLett.116.040502] showed theoretically that weak measurements are not a necessary condition to determine the weak value. Here, we report a measurement scheme used in a matter-wave interferometric experiment in which the neutron path system's quantum state was characterized via direct measurements, using both strong and weak interactions. Experimental evidence is given that strong interactions outperform weak ones for tomographic accuracy. Our results are not limited to neutron interferometry, but can be used in a wide range of quantum systems.
Nematollahi, Delaram; Zhang, Qimin; Altermatt, Joseph; Zhong, Shan; Goodman, Matthew; Bhagat, Anita; Schwettmann, Arne
2016-05-01
We present our apparatus designed to study matter-wave quantum optics in spin space, including our recently finished vacuum system and laser systems. Microwave-dressed spin-exchange collisions in a sodium spinor Bose-Einstein condensate provide a precisely controllable nonlinear interaction that generates squeezing and acts as a source of entanglement. As a consequence of this entanglement between atoms with magnetic quantum numbers m = +1 and m = -1, the noise of population measurements can be reduced below the shot noise. Versatile microwave pulse sequences will be used to implement an interferometer, a phase-sensitive amplifier and other devices. With an added ion detector to detect Rydberg atoms via pulsed-field ionization, we plan to study the effect of Rydberg excitations on the spin evolution of the ultracold gas.
On p-Wave Pairing Superconductivity under Cubic Symmetry : Condensed Matter and Statistical Physics
Masa-aki, OZAKI; Kazushige, MACHIDA; Tetsuo, OHMI; Department of Physics, Kyoto University
1985-01-01
A group theoretical classification of p-wave pairing superconducting states is made for a system with cubic crystalline symmetry in the absence of the spin-orbit coupling. The 15 inert p-pairing states which make the Ginzburg-Landau free energy stationary are enumerated and characterized, indicating that the energy gap vanishes along lines on the Fermi surface in some of those states. This is contrasted with the strong spin-orbit coupling case by others.
Goos-Hanchen-like shift of three-level matter wave incident on Raman beams
Duan, Zhenglu; Hu, Liyun; Xu, XueXiang; Liu, Cunjin
2013-01-01
When a three-level atomic wavepacket is obliquely incident on a "edium slab" consisting of two far-detuned laser beams, there exists lateral shift between reflection and incident points at the surface of a "medium slab", analogous to optical Goos-Hanchen effect. We evaluate lateral shifts for reflected and transmitted waves via expansion of reflection and transmission coefficients, in contrast to the stationary phase method. Results show that lateral shifts can be either positive or negative ...
Numerical Modelling of Wind Waves. Problems, Solutions, Verifications, and Applications
Polnikov, Vladislav
2011-01-01
The time-space evolution of the field is described by the transport equation for the 2-dimensional wave energy spectrum density, S(x,t), spread in the space, x, and time, t. This equation has the forcing named the source function, F, depending on both the wave spectrum, S, and the external wave-making factors: local wind, W(x, t), and local current, U(x, t). The source function contains certain physical mechanisms responsible for a wave spectrum evolution. It is used to distinguish three terms in function F: the wind-wave energy exchange mechanism, In; the energy conservative mechanism of nonlinear wave-wave interactions, Nl; and the wave energy loss mechanism, Dis. Differences in mathematical representation of the source function terms determine general differences between wave models. The problem is to derive analytical representations for the source function terms said above from the fundamental wave equations. Basing on publications of numerous authors and on the last two decades studies of the author, th...
A Novel Antimatter Detector with Application to Dark Matter Searches
Craig, W W; Fabris, L; Madden, N; Ziock, K; Hailey, C; Aramaki, T; Gabhauer, F; Koglin, J; Mori, K; Yu, H
2006-02-13
We report on recent accelerator testing of a prototype general antiparticle spectrometer (GAPS). GAPS uses a novel approach for indirect dark matter searches that exploits the antideuterons produced in neutralino-neutralino annihilations. GAPS captures these antideuterons into a target with the subsequent formation of exotic atoms. These exotic atoms decay with the emission of x-rays of precisely defined energy and a correlated pion signature from nuclear annihilation. This signature uniquely characterizes the antideuterons. Preliminary analysis of data from a prototype GAPS in an antiproton beam at the KEK accelerator in Japan has confirmed the multiple x-ray/pion star topology and indicated x-ray yields consistent with prior expectations. Moreover, our success in utilizing solid rather than gas targets represents a significant simplification over our original approach and offers potential gains in sensitivity through reduced dead mass in the target area.
Etienne Wamba; Timoléon C. Kofané; Alidou Mohamadou
2012-01-01
We construct,through a further extension of the tanh-function method,the matter-wave solutions of Bose-Einstein condensates (BECs) with a three-body interaction.The BECs are trapped in a potential comprising the linear magnetic and the time-dependent laser fields.The exact solutions obtained include soliton solutions,such as kink and antikink as well as bright,dark,multisolitonic modulated waves.We realize that the motion and the shape of the solitary wave can be manipulated by controlling the strengths of the fields.
Development and application of millimeter-wave imaging radar
Mase, Atsushi; Kogi, Yuichiro; Yamamoto, Akihide; Ohashi, Masamichi; Osako, Shuhei [Kyushu Univ., Advanced Science and Technology Center for Cooperative Research, Kasuga, Fukuoka (Japan); Bruskin, Leonid G. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Hojo, Hitoshi [Tsukuba Univ., Plasma Research Center, Tsukuba, Ibaraki (Japan)
2002-05-01
Significant advances in microwave and millimeter wave technology have enabled the development of a new generation of imaging diagnostics in this frequency region. Millimeter wave imaging radar is expected to be one of the most promising diagnostic methods for this purpose. It consists of a frequency-modulated continuous wave or pulsed wave as a probe beam and quasi-optical focusing optics followed by a planar-type detector array. We have started to develop a diagnostic system for the achievement of imaging radar. Representative experimental results obtained with related diagnostic systems are presented. (author)
Potential applications of low-energy shock waves in functional urology.
Wang, Hung-Jen; Cheng, Jai-Hong; Chuang, Yao-Chi
2017-08-01
A shock wave, which carries energy and can propagate through a medium, is a type of continuous transmitted sonic wave with a frequency of 16 Hz-20 MHz. It is accompanied by processes involving rapid energy transformations. The energy associated with shock waves has been harnessed and used for various applications in medical science. High-energy extracorporeal shock wave therapy is the most successful application of shock waves, and has been used to disintegrate urolithiasis for 30 years. At lower energy levels, however, shock waves have enhanced expression of vascular endothelial growth factor, endothelial nitric oxide synthase, proliferating cell nuclear antigen, chemoattractant factors and recruitment of progenitor cells; shock waves have also improved tissue regeneration. Low-energy shock wave therapy has been used clinically with musculoskeletal disorders, ischemic cardiovascular disorders and erectile dysfunction, through the mechanisms of neovascularization, anti-inflammation and tissue regeneration. Furthermore, low-energy shock waves have been proposed to temporarily increase tissue permeability and facilitate intravesical drug delivery. The present review article provides information on the basics of shock wave physics, mechanisms of action on the biological system and potential applications in functional urology. © 2017 The Japanese Urological Association.
Ionizing radiation effects on the matter and its applications in research and industry
Cruz Z, E. [Instituto de Ciencias Nucleares, UNAM, Ciudad Universitaria, Mexico 04510, D. F. (Mexico); Martinez B, G. [Laboratorio de Investigacion y Desarrollo de Materiales Avanzados, Facultad de Quimica, Universidad Autonoma del Estado de Mexico, Km. 12 Carretera Toluca-Atlacomulco, San Cayetano 50200, Estado de Mexico (Mexico)], e-mail: ecruz@nucleares.unam.mx
2009-07-01
Ionizing radiation as alpha and beta particles, electron accelerated, neutron particle, and X-rays and photons with relative high energy, as an useful radiation tool for many applications. the last two kind radiations are know as electromagnetic radiation. The radiation effects on the matter are well know that produces about fourteen processes during interaction with solids, aqueous solution and gases. In applications, commonly it depends of the nature and interest on the material samples that their characteristics can modify with the energy deposited on them. This part is devoted to more important effects produced by ionizing radiation with the matter and talk about the wide range applications recently; crystals radiation detectors and for application in medicine, detection of foodstuffs irradiated for preservation, and the application of ionizing radiation on polymeric materials. (Author)
Comparison between two models of absorption of matter waves by a thin time-dependent barrier
Barbier, Maximilien; Beau, Mathieu; Goussev, Arseni
2015-11-01
We report a quantitative, analytical, and numerical comparison between two models of the interaction of a nonrelativistic quantum particle with a thin time-dependent absorbing barrier. The first model represents the barrier by a set of time-dependent discontinuous matching conditions, which are closely related to Kottler boundary conditions used in stationary-wave optics as a mathematical basis for Kirchhoff diffraction theory. The second model mimics the absorbing barrier with an off-diagonal δ potential with a time-dependent amplitude. We show that the two models of absorption agree in their predictions in a semiclassical regime, the regime readily accessible in modern experiments with ultracold atoms.
Hospital electronic medical record enterprise application strategies: do they matter?
Fareed, Naleef; Ozcan, Yasar A; DeShazo, Jonathan P
2012-01-01
Successful implementations and the ability to reap the benefits of electronic medical record (EMR) systems may be correlated with the type of enterprise application strategy that an administrator chooses when acquiring an EMR system. Moreover, identifying the most optimal enterprise application strategy is a task that may have important linkages with hospital performance. This study explored whether hospitals that have adopted differential EMR enterprise application strategies concomitantly differ in their overall efficiency. Specifically, the study examined whether hospitals with a single-vendor strategy had a higher likelihood of being efficient than those with a best-of-breed strategy and whether hospitals with a best-of-suite strategy had a higher probability of being efficient than those with best-of-breed or single-vendor strategies. A conceptual framework was used to formulate testable hypotheses. A retrospective cross-sectional approach using data envelopment analysis was used to obtain efficiency scores of hospitals by EMR enterprise application strategy. A Tobit regression analysis was then used to determine the probability of a hospital being inefficient as related to its EMR enterprise application strategy, while moderating for the hospital's EMR "implementation status" and controlling for hospital and market characteristics. The data envelopment analysis of hospitals suggested that only 32 hospitals were efficient in the study's sample of 2,171 hospitals. The results from the post hoc analysis showed partial support for the hypothesis that hospitals with a best-of-suite strategy were more likely to be efficient than those with a single-vendor strategy. This study underscores the importance of understanding the differences between the three strategies discussed in this article. On the basis of the findings, hospital administrators should consider the efficiency associations that a specific strategy may have compared with another prior to moving toward
Acoustomicrofluidic application of quasi-shear surface waves.
Darinskii, A N; Weihnacht, M; Schmidt, H
2017-02-20
The paper analyzes the possibility of using predominantly boundary polarized surface acoustic waves for actuating fluidic effects in microchannels fabricated inside containers made of PDMS. The aim is to remove a shortcoming peculiar to conventionally utilized predominantly vertically polarized waves. Such waves strongly attenuate while they propagate under container side walls because of the leakage into them. Due to a specific feature of PDMS - extremely small shear elastic modulus - losses of boundary polarized modes should be far smaller. The amplitude of vertical mechanical displacements can be increased right inside the channel owing to the scattering of acoustic fields. As an example, the predominantly vertically polarized surface wave on 128YX LiNbO3 is compared with the quasi-shear leaky wave on 64YX LiNbO3. Our computations predict that, given the electric power supplied to the launching transducer, the quasi-shear wave will drive the fluid more efficiently than the surface wave on 128YX LiNbO3 when the container wall thickness is larger than 25-30 wavelengths, if there are no additional scatterers inside the channel. In the presence of a scatterer, such as a thin gold strip, the quasi-shear wave can be more efficient when the wall thickness exceeds 10-15 wavelengths.
Wave Simulation in Truncated Domains for Offshore Applications
Wellens, P.R.
2012-01-01
Guided-wave acousto-optics interactions, devices, and applications
1990-01-01
The field of integrated- or guided-wave optics has experienced significant and continuous growth since its inception in the late 1960s. There has been a considerable increase in research and development activity in this field worldwide and some significant advances in the realization of working in tegrated optic devices and modules have been made in recent years. In fact, there have already been some commercial manufacturing and technical ap plications of such devices and modules. The guided-wave-acoustooptics involving Bragg interactions between guided optical waves and surface acoustic waves is one of the areas of in tegrated-optics that has reached some degree of scientific and technological maturity. This topical volume is devoted to an in-depth treatment of this emerging branch of science and technology. Presented in this volume are concise treatments on bulk-wave acoustooptics, guided-wave optics, and surface acoustic waves, and detailed studies of guided-wave acoustooptic Bragg diffraction in thr...
Wave Simulation in Truncated Domains for Offshore Applications
Wellens, P.R.
2012-01-01
2010-04-23
... Energy Regulatory Commission Oregon Wave Energy Partners I, LLC; Notice of Preliminary Permit Application..., 2010. On March 2, 2010, Oregon Wave Energy Partners I, LLC filed an application for a subsequent.... Applicant Contact: Mr. Charles F. Dunleavy, Oregon Wave Energy Partners I, LLC, 1590 Reed Road,...
Applications of High-Frequency Gravitational Waves to the Global War on Terror
Baker, Robert M. L.
2010-01-01
Applications of high-frequency gravitational waves or HFGWs to the global war on terror are now realistic because technology developed by GravWave® LLC and other institutions overseas can lead to devices, some already constructed, that can generate and detect HFGWs. In fact, three HFGW detectors have been built outside the United States and an ultra high-sensitive Li-Baker HFGW Detector has been proposed. HFGW generators have been proposed theoretically by the Russians, Germans, Italians and Chinese. Because of their unique characteristics, such as their ability to pass through all material without attenuation, HFGWs could be utilized for uninterruptible, very low-probability-of-intercept (LPI), high-bandwidth communications among and between anti-terrorist assets. One such communications system, which can be constructed from off-the-shelf elements, is discussed. The HFGW generation device or transmitter alternative selected is based upon bands of piezoelectric crystal, film-bulk acoustic resonators or FBARs energized by conventional Magnetrons. The system is theoretically capable of transmitting and detecting, through use of the Li-Baker HFGW detector, a signal generated on the opposite side of the Earth. Although HFGWs do not interact with and are not absorbed by ordinary matter, their presence can be detected by their distortion of spacetime as measured by the Laser Interferometer Gravitational Observatory (LIGO), Virgo, GEO600, et al., by detection photons generated from electromagnetic beams having the same frequency, direction and phase as the HFGWs in a superimposed magnetic field (Li-Baker HFGW Detector), by the change in polarization HFGWs produce in a microwave guide (Birmingham University Detector) and by other such instruments. Potential theoretical applications, which may or may not be practical yet theoretically possible, are propulsion, including "moving" space objects such as missiles, anti-missiles and warheads in flight; surveillance through
Modelling wave-boundary layer interaction for wind power applications
Jenkins, A. D.; Barstad, I.; Gupta, A.; Adakudlu, M.
2012-04-01
Marine wind power production facilities are subjected to direct and indirect effects of ocean waves. Direct effects include forces due to wave orbital motions and slamming of the water surface under breaking wave conditions, corrosion and icing due to sea spray, and the effects of wave-generated air bubbles. Indirect effects include include the influence of waves on the aerodynamic sea-surface roughness, air turbulence, the wind velocity profile, and air velocity oscillations, wave-induced currents and sediment transport. Field observations within the boundary layers from floating measurement may have to be corrected to account for biases induced as a result of wave-induced platform motions. To estimate the effect of waves on the atmospheric boundary layer we employ the WRF non-hydrostatic mesoscale atmosphere model, using the default YSU planetary boundary layer (PBL) scheme and the WAM spectral wave model, running simultaneously and coupled using the open-source coupler MCEL which can interpolate between different model grids and timesteps. The model is driven by the WRF wind velocity at 10 m above the surface. The WRF model receives from WAM updated air-sea stress fields computed from the wind input source term, and computes new fields for the Charnock parameter and marine surface aerodynamic roughness. Results from a North Atlantic and Nordic Seas simulation indicate that the two-way coupling scheme alters the 10 metre wind predicted by WRF by up to 10 per cent in comparison with a simulation using a constant Charnock parameter. The changes are greatest in developing situations with passages of fronts, moving depressions and squalls. This may be directly due to roughness length changes, or may be due to changes in the timing of front/depression/squall passages. Ongoing work includes investigating the effect of grid refinement/nesting, employing different PBL schemes, and allowing the wave field to change the direction of the total air-sea stress.
Gravitational waves in dynamical spacetimes with matter content in the Fully Constrained Formulation
Cordero-Carrión, Isabel; Ibáñez, José María
2011-01-01
The Fully Constrained Formulation (FCF) of General Relativity is a novel framework introduced as an alternative to the hyperbolic formulations traditionally used in numerical relativity. The FCF equations form a hybrid elliptic-hyperbolic system of equations including explicitly the constraints. We present an implicit-explicit numerical algorithm to solve the hyperbolic part, whereas the elliptic sector shares the form and properties with the well known Conformally Flat Condition (CFC) approximation. We show the stability andconvergence properties of the numerical scheme with numerical simulations of vacuum solutions. We have performed the first numerical evolutions of the coupled system of hydrodynamics and Einstein equations within FCF. As a proof of principle of the viability of the formalism, we present 2D axisymmetric simulations of an oscillating neutron star. In order to simplify the analysis we have neglected the back-reaction of the gravitational waves into the dynamics, which is small (<2 %) for ...
Schematic way to find solution of the outcoupled matter wave with a source term
Prayitno, T. B. [Physics Department, Faculty of Mathematics and Natural Science, Universitas Negeri Jakarta, Jl. Pemuda Rawamangun No. 10, Jakarta, 13220 (Indonesia)
2013-09-09
We propose a schematic way to obtain solution of the outcoupled atom laser beam wave function in the presence of a source term where the beam is influenced by gravity. In this case, we only focus on the external potentials inside the region of Bose-Einstein condensate that are generated by electromagnetic source and gravity. Since the evolution of the atom laser beam can be portrayed through the ordinary Schrödinger equation with a source, we are allowed to express the general solution as the superposition of the homogeneous solution and particular solution. With the given external potentials and ansatz solutions, we attain that the obtained energy depends on the parameter constituting to the ratio between the longitudinal frequency and transverse frequency.
Group theory Application to the physics of condensed matter
Dresselhauss, M S; Jorio, A
2007-01-01
Every process in physics is governed by selection rules that are the consequence of symmetry requirements. The beauty and strength of group theory resides in the transformation of many complex symmetry operations into a very simple linear algebra. This concise and class-tested book has been pedagogically tailored over 30 years MIT and 2 years at the University Federal of Minas Gerais (UFMG) in Brazil. The approach centers on the conviction that teaching group theory in close connection with applications helps students to learn, understand and use it for their own needs. For this reason, the theoretical background is confined to the first 4 introductory chapters (6-8 classroom hours). From there, each chapter develops new theory while introducing applications so that the students can best retain new concepts, build on concepts learned the previous week, and see interrelations between topics as presented. Essential problem sets between the chapters also aid the retention of the new material and for the consolid...
Seismic waves estimation and wavefield decomposition: application to ambient vibrations
Maranò, Stefano; Reller, Christoph; Loeliger, Hans-Andrea; Fäh, Donat
2012-10-01
Passive seismic surveying methods represent a valuable tool in local seismic hazard assessment, oil and gas prospection, and in geotechnical investigations. Array processing techniques are used in order to estimate wavefield properties such as dispersion curves of surface waves and ellipticity of Rayleigh waves. However, techniques presently in use often fail to properly merge information from three-components sensors and do not account for the presence of multiple waves. In this paper, a technique for maximum likelihood estimation of wavefield parameters including direction of propagation, velocity of Love waves and Rayleigh waves, and ellipticity of Rayleigh waves is described. This technique models jointly all the measurements and all the wavefield parameters. Furthermore it is possible to model the simultaneous presence of multiple waves. The performance of this technique is evaluated on a high-fidelity synthetic data set and on real data. It is shown that the joint modelling of all the sensor components, decreases the variance of wavenumber estimates and allows the retrieval of the ellipticity value together with an estimate of the prograde/retrograde motion.
Generation of Focused Shock Waves in Water for Biomedical Applications
Lukeš, Petr; Šunka, Pavel; Hoffer, Petr; Stelmashuk, Vitaliy; Beneš, Jiří; Poučková, Pavla; Zadinová, Marie; Zeman, Jan
The physical characteristics of focused two-successive (tandem) shock waves (FTSW) in water and their biological effects are presented. FTSW were generated by underwater multichannel electrical discharges in a highly conductive saline solution using two porous ceramic-coated cylindrical electrodes of different diameter and surface area. The primary cylindrical pressure wave generated at each composite electrode was focused by a metallic parabolic reflector to a common focal point to form two strong shock waves with a variable time delay between the waves. The pressure field and interaction between the first and the second shock waves at the focus were investigated using schlieren photography and polyvinylidene fluoride (PVDF) shock gauge sensors. The largest interaction was obtained for a time delay of 8-15 μs between the waves, producing an amplitude of the negative pressure phase of the second shock wave down to -80 MPa and a large number of cavitations at the focus. The biological effects of FTSW were demonstrated in vitro on damage to B16 melanoma cells, in vivo on targeted lesions in the thigh muscles of rabbits and on the growth delay of sarcoma tumors in Lewis rats treated in vivo by FTSW, compared to untreated controls.
Gidel, Floriane; Bokhove, Onno; Kalogirou, Anna
2017-01-01
In this work, we model extreme waves that occur due to Mach reflection through the intersection of two obliquely incident solitary waves. For a given range of incident angles and amplitudes, the Mach stem wave grows linearly in length and amplitude, reaching up to 4 times the amplitude of the incident waves. A variational approach is used to derive the bidirectional Benney-Luke equations, an asymptotic equivalent of the three-dimensional potential-flow equations modelling water waves. This nonlinear and weakly dispersive model has the advantage of allowing wave propagation in two horizontal directions, which is not the case with the unidirectional Kadomtsev-Petviashvili (KP) equation used in most previous studies. A variational Galerkin finite-element method is applied to solve the system numerically in Firedrake with a second-order Störmer-Verlet temporal integration scheme, in order to obtain stable simulations that conserve the overall mass and energy of the system. Using this approach, we are able to get close to the 4-fold amplitude amplification predicted by Miles.
Significant wave heights from Sentinel-1 SAR: Validation and applications
Stopa, J. E.; Mouche, A.
2017-03-01
Two empirical algorithms are developed for wave mode images measured from the synthetic aperture radar aboard Sentinel-1 A. The first method, called CWAVE_S1A, is an extension of previous efforts developed for ERS2 and the second method, called Fnn, uses the azimuth cutoff among other parameters to estimate significant wave heights (Hs) and average wave periods without using a modulation transfer function. Neural networks are trained using colocated data generated from WAVEWATCH III and independently verified with data from altimeters and in situ buoys. We use neural networks to relate the nonlinear relationships between the input SAR image parameters and output geophysical wave parameters. CWAVE_S1A performs well and has reduced precision compared to Fnn with Hs root mean square errors within 0.5 and 0.6 m, respectively. The developed neural networks extend the SAR's ability to retrieve useful wave information under a large range of environmental conditions including extratropical and tropical cyclones in which Hs estimation is traditionally challenging.Plain Language SummaryTwo empirical algorithms are developed to estimate integral wave parameters from high resolution synthetic aperture radar (SAR) ocean images measured from recently launched the Sentinel 1 satellite. These methods avoid the use of the complicated image to wave mapping typically used to estimate sea state parameters. In addition, we are able to estimate wave parameters that are not able to be measured using existing techniques for the Sentinel 1 satellite. We use a machine learning technique to create a model that relates the ocean image properties to geophysical wave parameters. The models are developed using data from a numerical model because of the sufficiently large sample of global ocean conditions. We then verify that our developed models perform well with respect to independently measured wave observations from other satellite sensors and buoys. We successfully created models that
Application of local wave time-frequency method in reciprocating mechanical fault diagnosis
Wang Lei; Wang Fengtao; Ma Xiaojiang
2006-01-01
To diagnose the reciprocating mechanical fault. We utilized local wave time-frequency approach. Firstly,we gave the principle. Secondly, the application of local wave time-frequency was given. Finally, we discussed its virtue in reciprocating mechanical fault diagnosis.
Surface wave scattering theory : with applications to forward and inverse problems in seismology
Snieder, R.K.
1987-01-01
Scattering of surface waves in a three dimensional layered elastic medium with embedded heterogeneities is described in this thesis with the Born approximation. The dyadic decomposition of the surface wave Green's function provides the crucial element for an efficient application of Born theory to s
ADAPTIVE OUTPUT CONTROL: SUBJECT MATTER, APPLICATION TASKS AND SOLUTIONS
Alexey A. Bobtsov
2013-01-01
Full Text Available The problem of adaptive output control for parametric and functionally uncertain plants is considered. Application examples illustrating the practical use of the discussed theory are given along with the mathematical formulation of the problem. A brief review of adaptive output control methods, by both linear and non-linear systems, is presented and an extensive bibliography, in which the reader will find a detailed description of the specific algorithms and their properties, is represented. A new approach to the output control problem - a method of consecutive compensator - is considered in detail.
Study of a tissue protecting system for clinical applications of underwater shock wave
Hosseini, S. H. R.; Takayama, Kazuyoshi
2005-04-01
Applications of underwater shock waves have been extended to various clinical therapies during the past two decades. Besides the successful contribution of extracorporeal shock waves, tissue damage especially to the vasculature has been reported. These side effects are believed to be due to the shock wave-tissue interaction and cavitation. In the present research in order to minimize shock wave induced damage a shock wave attenuating system was designed and studied. The attenuating system consisted of thin gas packed layers immersed in water, which could attenuate more than 90% of shock waves overpressure. Silver azide micro-pellets (10 mg) were ignited by irradiation of a pulsed Nd:YAG laser to generate shock waves. Pressure histories were measured with fiber optic probe and PVDF needle hydrophones. The strength of incident shock waves was changed by adjusting the distance between the pellets and the layers. The whole sequences of the shock wave attenuation due to the interaction of shock waves with the dissipating layers were quantitatively visualized by double exposure holographic interferometry and time resolved high speed photography. The attenuated shock had overpressure less than threshold damage of brain tissue evaluated from histological examination of the rat brain treated by shock waves.
Piezoresistive Soft Condensed Matter Sensor for Body-Mounted Vital Function Applications.
Melnykowycz, Mark; Tschudin, Michael; Clemens, Frank
2016-03-04
A soft condensed matter sensor (SCMS) designed to measure strains on the human body is presented. The hybrid material based on carbon black (CB) and a thermoplastic elastomer (TPE) was bonded to a textile elastic band and used as a sensor on the human wrist to measure hand motion by detecting the movement of tendons in the wrist. Additionally it was able to track the blood pulse wave of a person, allowing for the determination of pulse wave peaks corresponding to the systole and diastole blood pressures in order to calculate the heart rate. Sensor characterization was done using mechanical cycle testing, and the band sensor achieved a gauge factor of 4-6.3 while displaying low signal relaxation when held at a strain levels. Near-linear signal performance was displayed when loading to successively higher strain levels up to 50% strain.
The collapse of the wave function in the joint metric-matter quantization for inflation
Diez-Tejedor, Alberto; Sudarsky, Daniel
2011-01-01
It has been argued that the standard inflationary scenario suffers from a serious deficiency as a model for the origin of the seeds of cosmic structure: it can not truly account for the transition from an early homogeneous and isotropic stage to another one lacking such symmetries. The issue has often been thought as a standard instance of the "quantum measurement problem", but as has been recently argued by some of us the situation reaches a critical level in the cosmological context of interest here. This has lead to a proposal in which the standard paradigm is supplemented by a hypothesis concerning the self-induced dynamical collapse of the wave function, as representing the physical mechanism through which such change of symmetry is brought forth. This proposal was formulated within the context of semiclassical gravity. Here we investigate an alternative realization of such idea implemented directly within the standard analysis in terms of a quantum field jointly describing the inflaton and metric pertur...
Application of Maximum Entropy Distribution to the Statistical Properties of Wave Groups
无
2007-01-01
The new distributions of the statistics of wave groups based on the maximum entropy principle are presented. The maximum entropy distributions appear to be superior to conventional distributions when applied to a limited amount of information. Its applications to the wave group properties show the effectiveness of the maximum entropy distribution. FFT filtering method is employed to obtain the wave envelope fast and efficiently. Comparisons of both the maximum entropy distribution and the distribution of Longuet-Higgins (1984) with the laboratory wind-wave data show that the former gives a better fit.
Near-Shore Floating Wave Energy Converters:applications for coastal protection
Ruol, Piero; Zanuttigh, Barbara; Martinelli, Luca; Kofoed, Jens Peter; Frigaard, Peter
2010-01-01
Aim of this note is to analyse the possible application of a Wave Energy Converter (WEC) as a combined tool to protect the coast and harvest energy. Physical model tests are used to evaluate wave transmission past a near-shore floating WEC of the wave activated body type, named DEXA. Efficiency and transmission characteristics are approximated to functions of wave height, period and obliquity. Their order of magnitude are 20% and 80%, respectively. It is imagined that an array of DEXA is depl...
Mass sensitivity of layered shear-horizontal surface acoustic wave devices for sensing applications
Kalantar-Zadeh, Kourosh; Trinchi, Adrian; Wlodarski, Wojtek; Holland, Anthony; Galatsis, Kosmas
2001-11-01
Layered Surface Acoustic Wave (SAW) devices that allow the propagation of Love mode acoustic waves will be studied in this paper. In these devices, the substrate allows the propagation of Surface Skimming Bulks Waves (SSBWs). By depositing layers, that the speed of Shear Horizontal (SH) acoustic wave propagation is less than that of the substrate, the propagation mode transforms to Love mode. Love mode devices which will be studied in this paper, have SiO2 and ZnO acoustic guiding layers. As Love mode of propagation has no movement of particles component normal to the active sensor surface, they can be employed for the sensing applications in the liquid media.
Li, Bohua; Shapiro, Paul R.; Rindler-Daller, Tanja
2017-01-01
We consider an alternative to WIMP cold dark matter (CDM), ultralight bosonic dark matter (m≥10-22 eV) described by a complex scalar field (SFDM), of which the comoving particle number density is conserved after particle production during standard reheating (w=p/ρ=0). In a ΛSFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiation-like (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the familiar radiation-dominated phase, there is an even earlier phase of stiff-SFDM-domination, during which the expansion rate is higher than in ΛCDM. The transitions between these phases, determined by SFDM particle mass m, and coupling strength λ, of a quartic self-interaction, are therefore constrained by cosmological observables, particularly Neff, the effective number of neutrino species during BBN, and zeq, the redshift of matter-radiation equality. Furthermore, since the homogeneous energy density contributed by the stochastic gravitational wave background (SGWB) from inflation is amplified during the stiff phase, relative to the other components, the SGWB can contribute a radiation-like component large enough to affect these observables. This same amplification makes possible detection of this SGWB at high frequencies by current laser interferometer experiments, e.g., aLIGO/Virgo, eLISA. For SFDM particle parameters that satisfy these cosmological constraints, the amplified SGWB is detectable by aLIGO, for values of tensor-to-scalar ratio r currently allowed by CMB polarization measurements, for a broad range of possible reheat temperatures Tre. For a given r, if SFDM parameters marginally satisfy cosmological constraints (maximizing total SGWB energy density), the SGWB is maximally detectable when modes that reenter the horizon when reheating ends have frequencies in the 10-50 Hz aLIGO band today. For example, if r=0.01, the maximally detectable model for (λ/(mc2)2, m)=(10-18 eV-1cm3, 8×10-20 eV) has Tre=104 GeV, for
Tandem shock waves in medicine and biology: a review of potential applications and successes
Lukes, P.; Fernández, F.; Gutiérrez-Aceves, J.; Fernández, E.; Alvarez, U. M.; Sunka, P.; Loske, A. M.
2016-01-01
Shock waves have been established as a safe and effective treatment for a wide range of diseases. Research groups worldwide are working on improving shock wave technology and developing new applications of shock waves to medicine and biology. The passage of a shock wave through soft tissue, fluids, and suspensions containing cells may result in acoustic cavitation i.e., the expansion and violent collapse of microbubbles, which generates secondary shock waves and the emission of microjets of fluid. Cavitation has been recognized as a significant phenomenon that produces both desirable and undesirable biomedical effects. Several studies have shown that cavitation can be controlled by emitting two shock waves that can be delayed by tenths or hundreds of microseconds. These dual-pulse pressure pulses, which are known as tandem shock waves, have been shown to enhance in vitro and in vivo urinary stone fragmentation, cause significant cytotoxic effects in tumor cells, delay tumor growth, enhance the bactericidal effect of shock waves and significantly increase the efficiency of genetic transformations in bacteria and fungi. This article provides an overview of the basic physical principles, methodologies, achievements and potential uses of tandem shock waves to improve biomedical applications.
Mishima, Takashi; Tomizawa, Shinya
2017-07-01
To clarify certain nonlinear properties of strong gravitational field, we investigate cylindrically symmetric gravitational waves that are localized as regular wave packets in the space of radial and time coordinates. The waves are constructed by applying a certain kind of harmonic mapping method to the seed solutions with linear polarization, which are generalizations of the solution representing a cylindrical gravitational pulse wave discussed by Weber, Wheeler, and Bonnor. The solutions obtained here, though their form is rather simple, show occurrence of strong mutual conversion between a linear mode and a cross mode apparently. The single localized wave shows the conversion in the vicinity of the symmetric axis where the self-interaction is strengthened, and the collision between multiple waves also causes the conversion. These phenomena can be thought to be the emergence of genuine nonlinearity that the Einstein gravity holds. Finally we discuss a simple, but interesting application of the solutions to the case of the Einstein-Maxwell system.
Planar millimeter wave radar frontend for automotive applications
J. Grubert
2003-01-01
Full Text Available A fully integrated planar sensor for 77 GHz automotive applications is presented. The frontend consists of a transceiver multichip module and an electronically steerable microstrip patch array. The antenna feed network is based on a modified Rotman-lens and connected to the array in a multilayer approach offering higher integration. Furthermore, the frontend comprises a phase lock loop to allow proper frequency-modulated continuous wave (FMCW radar operation. The latest experimental results verify the functionality of this advanced frontend design featuring automatic cruise control, precrash sensing and cut-in detection. These promising radar measurements give reason to a detailed theoretical investigation of system performance. Employing commercially available MMIC various circuit topologies are compared based on signal-tonoise considerations. Different scenarios for both sequential and parallel lobing hint to more advanced sensor designs and better performance. These improvements strongly depend on the availability of suitable MMIC and reliable packaging technologies. Within our present approach possible future MMIC developments are already considered and, thus, can be easily adapted by the flexible frontend design. Es wird ein integrierter planarer Sensor für 77 GHz Radaranwendungen vorgestellt. Das Frontend besteht aus einem Sende- und Empfangs-Multi-Chip-Modul und einer elektronisch schwenkbaren Antenne. Das Speisenetzwerk der Antenne basiert auf einer modifizierten Rotman- Linse. Für eine kompakte Bauweise sind Antenne und Speisenetzwerk mehrlagig integriert. Weiterhin umfasst das Frontend eine Phasenregelschleife für eine präzise Steuerung des frequenzmodulierten Dauerstrichradars. Die aktuellen Messergebnisse bestätigen die Funktionalit¨at dieses neuartigen Frontend-Designs, das automatische Geschwindigkeitsregelung, Kollisionswarnung sowie Nahbereichsüberwachung ermöglicht. Die Qualität der Messergebnisse hat weiterf
Planar millimeter wave radar frontend for automotive applications
Grubert, J.; Heyen, J.; Metz, C.; Stange, L. C.; Jacob, A. F.
2003-05-01
A fully integrated planar sensor for 77 GHz automotive applications is presented. The frontend consists of a transceiver multichip module and an electronically steerable microstrip patch array. The antenna feed network is based on a modified Rotman-lens and connected to the array in a multilayer approach offering higher integration. Furthermore, the frontend comprises a phase lock loop to allow proper frequency-modulated continuous wave (FMCW) radar operation. The latest experimental results verify the functionality of this advanced frontend design featuring automatic cruise control, precrash sensing and cut-in detection. These promising radar measurements give reason to a detailed theoretical investigation of system performance. Employing commercially available MMIC various circuit topologies are compared based on signal-tonoise considerations. Different scenarios for both sequential and parallel lobing hint to more advanced sensor designs and better performance. These improvements strongly depend on the availability of suitable MMIC and reliable packaging technologies. Within our present approach possible future MMIC developments are already considered and, thus, can be easily adapted by the flexible frontend design. Es wird ein integrierter planarer Sensor für 77 GHz Radaranwendungen vorgestellt. Das Frontend besteht aus einem Sende- und Empfangs-Multi-Chip-Modul und einer elektronisch schwenkbaren Antenne. Das Speisenetzwerk der Antenne basiert auf einer modifizierten Rotman- Linse. Für eine kompakte Bauweise sind Antenne und Speisenetzwerk mehrlagig integriert. Weiterhin umfasst das Frontend eine Phasenregelschleife für eine präzise Steuerung des frequenzmodulierten Dauerstrichradars. Die aktuellen Messergebnisse bestätigen die Funktionalit¨at dieses neuartigen Frontend-Designs, das automatische Geschwindigkeitsregelung, Kollisionswarnung sowie Nahbereichsüberwachung ermöglicht. Die Qualität der Messergebnisse hat weiterführende theoretische
Generalized and exact solutions for oblique shock waves of real gases with application to real air
Kouremenos, D. A.; Antonopoulos, K. A.
1989-12-01
The present work presents a generalized method for calculating oblique shock waves of real gases, based on the Redlich-Kwong (1949) equation of state. Also described is an exact method applicable when the exact equation of state and enthalpy function of a real gas are available. Application of the generalized and the exact methods in the case of real air showed that the former is very accurate and at least twenty times faster than the latter. An additional contribution of the study is the derivation of real gas oblique shock wave equations, which are of the same algebraic form as the well known ideal gas normal shock wave relations.
Propagation of elastic waves through textured polycrystals: application to ice.
Maurel, Agnès; Lund, Fernando; Montagnat, Maurine
2015-05-08
The propagation of elastic waves in polycrystals is revisited, with an emphasis on configurations relevant to the study of ice. Randomly oriented hexagonal single crystals are considered with specific, non-uniform, probability distributions for their major axis. Three typical textures or fabrics (i.e. preferred grain orientations) are studied in detail: one cluster fabric and two girdle fabrics, as found in ice recovered from deep ice cores. After computing the averaged elasticity tensor for the considered textures, wave propagation is studied using a wave equation with elastic constants c=〈c〉+δc that are equal to an average plus deviations, presumed small, from that average. This allows for the use of the Voigt average in the wave equation, and velocities are obtained solving the appropriate Christoffel equation. The velocity for vertical propagation, as appropriate to interpret sonic logging measurements, is analysed in more details. Our formulae are shown to be accurate at the 0.5% level and they provide a rationale for previous empirical fits to wave propagation velocities with a quantitative agreement at the 0.07-0.7% level. We conclude that, within the formalism presented here, it is appropriate to use, with confidence, velocity measurements to characterize ice fabrics.
Nearly non-scattering electromagnetic wave set and its application
Liu, Hongyu; Wang, Yuliang; Zhong, Shuhui
2017-04-01
For any inhomogeneous compactly supported electromagnetic (EM) medium, it is shown that there exists an infinite set of linearly independent EM waves which generate nearly vanishing scattered wave fields. If the inhomogeneous medium is coated with a layer of properly chosen conducting medium, then the wave set is generated from the Maxwell-Herglotz approximation to the interior perfectly electric conducting or perfectly magnetic conducting eigenfunctions and depends only on the shape of the inhomogeneous medium. If no such a conducting coating is used, then the wave set is generated from the Maxwell-Herglotz approximation to the generalised interior transmission eigenfunctions and depends on both the content and shape of the inhomogeneous medium. We characterise the nearly non-scattering wave sets in both cases with sharp estimates. The results can be used to give a conceptual design of a novel shadowless lamp. The crucial ingredient is to properly choose the source of the lamp so that nearly no shadow will be produced by surgeons operating under the lamp.
Application of Generalized Lamb Wave for Evaluation of Coating Layers
Kwon, Sung Duk [Andong National University, Andong (Korea, Republic of); Kim, Hak Joon; Song, Sung Jin [Sungkyunkwan University, Suwon (Korea, Republic of)
2007-06-15
This work is aimed to explore a possibility of using the generalized Lamb waves for nondestructive evaluation of the bonding quality of layered substrates. For this purpose, we prepared two sets of specimens with imperfect bonding at their interfaces; 1) TiN-coated specimens with various wear conditions, and 2) CVD diamond specimens with various cleaning conditions. A dispersion simulation performed for layered substrates with imperfect interfaces are carried out to get the characteristics of dispersion curves that can be used for bonding quality evaluation. Then the characteristics of dispersion curves of the fabricated specimens are experimentally determined by use of an ultrasonic backward radiation measurement technique. The results obtained in the present study show that the lowest velocity mode (Rayleigh-like) of the generalized Lamb waves are sensitively affected by the bonding quality. Therefore, the generalized Lamb waves can be applied for nondestructive evaluation of imperfect bonding quality in various layered substrates
Application of singular perturbation method in analyzing traffic density waves
SHEN Fei-ying; GE Hong-xia; LEI Li
2009-01-01
Car following model is one of microscopic models for describing traffic flow. Through linear stability analysis, the neutral stability lines and the critical points are obtained for the different types of car following models and two modified models. The singular perturbation method has been used to derive various nonlinear wave equations, such as the Korteweg-de-Vries (KdV) equation and the modified Korteweg-de-Vries (mKdV) equation, which could describe different density waves occurring in traffic flows under certain conditions. These density waves are mainly employed to depict the formation of traffic jams in the congested traffic flow. The general soliton solutions are given for the different types of car following models, and the results have been used to the modified models efficiently.
Thermal sensitivity of Lamb waves for structural health monitoring applications.
Dodson, J C; Inman, D J
2013-03-01
One of the drawbacks of the current Lamb wave structural health monitoring methods are the false positives due to changing environmental conditions such as temperature. To create an environmental insensitive damage detection scheme, the physics of thermal effects on Lamb waves must be understood. Dispersion and thermal sensitivity curves for an isotropic plate with thermal stress and thermally varying elastic modulus are presented. The thermal sensitivity of dispersion curves is analytically developed and validated by experimental measurements. The group velocity thermal sensitivity highlights temperature insensitive features at two critical frequencies. The thermal sensitivity gives us insight to how temperature affects Lamb wave speeds in different frequency ranges and will help those developing structural health monitoring algorithms.
Structural Reliability of Plain Bearings for Wave Energy Converter Applications
Ambühl, Simon; Kramer, Morten Mejlhede; Sørensen, John Dalsgaard
2016-01-01
The levelized cost of energy (LCOE) from wave energy converters (WECs) needs to be decreased in order to be able to become competitive with other renewable electricity sources. Probabilistic reliability methods can be used to optimize the structure of WECs. Optimization is often performed...... the hydraulic cycle when waves are passing. The new PTO system leads to different load characteristics at the floater itself compared to the actual setup where the turbine/generator is directly coupled to the fluctuating hydraulic pressure within the PTO system. This paper calculates the structural reliability...
Pulse mode operation of Love wave devices for biosensing applications
Newton, MI; McHale, G; Martin, F; Gizeli, E.; Melzak, KA
2001-01-01
In this work we present a novel pulse mode Love wave biosensor that monitors both changes in amplitude and phase. A series of concentrations of 3350 molecular weight poly(ethylene glycol) (PEG) solutions are used as a calibration sequence for the pulse mode system using a network analyzer and high frequency oscilloscope. The operation of the pulse mode system is then compared to the continuous wave network analyzer by showing a sequence of deposition and removal of a model mass layer of palmi...
Gurbatov, S N; Saichev, A I
2012-01-01
"Waves and Structures in Nonlinear Nondispersive Media: General Theory and Applications to Nonlinear Acoustics” is devoted completely to nonlinear structures. The general theory is given here in parallel with mathematical models. Many concrete examples illustrate the general analysis of Part I. Part II is devoted to applications to nonlinear acoustics, including specific nonlinear models and exact solutions, physical mechanisms of nonlinearity, sawtooth-shaped wave propagation, self-action phenomena, nonlinear resonances and engineering application (medicine, nondestructive testing, geophysics, etc.). This book is designed for graduate and postgraduate students studying the theory of nonlinear waves of various physical nature. It may also be useful as a handbook for engineers and researchers who encounter the necessity of taking nonlinear wave effects into account of their work. Dr. Gurbatov S.N. is the head of Department, and Vice Rector for Research of Nizhny Novgorod State University. Dr. Rudenko O.V. is...
无
2007-01-01
Surface waves comprise an important aspect of the interaction between the atmosphere and the ocean, so a dynamically consistent framework for modelling atmosphere-ocean interaction must take account of surface waves, either implicitly or explicitly. In order to calculate the effect of wind forcing on waves and currents, and vice versa, it is necessary to employ a consistent formulation of the energy and momentum balance within the airflow, wave field, and water column. It is very advantageous to apply surface-following coordinate systems, whereby the steep gradients in mean flow properties near the air-water interface in the cross-interface direction may be resolved over distances which are much smaller than the height of the waves themselves. We may account for the waves explicitly by employing a numerical spectral wave model, and applying a suitable theory of wave-mean flow interaction. If the mean flow is small compared with the wave phase speed, perturbation expansions of the hydrodynamic equations in a Lagrangian or generalized Lagrangian mean framework are useful: for stronger flows, such as for wind blowing over waves, the presence of critical levels where the mean flow velocity is equal to the wave phase speed necessitates the application of more general types of surface-following coordinate system. The interaction of the flow of air and water and associated differences in temperature and the concentration of various substances (such as gas species) gives rise to a complex boundary-layer structure at a wide range of vertical scales, from the sub-millimetre scales of gaseous diffusion, to several tens of metres for the turbulent Ekman layer. The balance of momentum, heat, and mass is also affected significantly by breaking waves, which act to increase the effective area of the surface for mass transfer, and increase turbulent diffusive fluxes via the conversion of wave energy to turbulent kinetic energy.
Kudriavtcev, Iurii
2015-01-01
We explore the possibility to give a classical explanation to the specifics and physical sense of de Broglie matter waves when studying the microparticle as an object of non zero size, from the point of view of the special theory of relativity. We show that the particularities of de Broglie matter waves and the results of the experimental verifications of Bell inequalities for the pairs of entangled photons are naturally interpreted as the results of implementation of the conclusions of the special theory of relativity to the microparticles. We conclude that it is appropriate to go back to the search of the new means of realistic description of the nature proposed by Einstein and his realistic worldview that states that the world studied by the science is real and every part of it at any moment of time has objective physical characteristics.
Ibsen, Lars Bo
2008-01-01
Estimates for the amount of potential wave energy in the world range from 1-10 TW. The World Energy Council estimates that a potential 2TW of energy is available from the world’s oceans, which is the equivalent of twice the world’s electricity production. Whilst the recoverable resource is many t...
Design of continuous long slot leaky-wave antenna for millimeter wave application
Lü Shanwei; Zhang Yan; Liu Juan; Zhang Jiangling
2007-01-01
A simple and efficient design scheme of the continuous long slot leaky-wave antenna is developed. The key steps involved in the scheme are summarized. First, the cut-off frequencies of slot waveguides with different slot offsets are obtained by 3D finite-difference time-domain (FDTD) method. Second, the attenuation function αra is estimated by the aperture distribution, and the attenuation function αrs is determined by the slot radiation.Finally, the attenuation function αra is combined with the attenuation function αrs by the coefficient K. And an example in Ka band is presented. Moreover, the return loss of the E-plane Tee-junction (ET) and the radiation pattern of leaky-wave antenna are simulated. The scheme is verified by comparing with the experimental result.
Thalmayr, Florian; Hashimoto, Ken-Ya; Omori, Tatsuya; Yamaguchi, Masatsune
2010-07-01
This paper demonstrates a novel frequency domain analysis (FDA) to evaluate the scattering behavior of a waveguide mode at arbitrary scattering geometries by a time harmonic simulation based on the finite element method (FEM). To this end, we add an injection-damping mechanism (IDM) to avoid interference at the acoustic input port. The IDM can be easily constructed by a numerical operation. Our approach offers improved time consumption and calculation power necessary over the established method in the time domain. After checking the validity of the proposed method, we discuss the importance of considering wave scattering phenomena in film bulk acoustic wave resonator (FBAR) devices by applying the proposed method to two simplified models of an FBAR device.
Wave motion as inquiry the physics and applications of light and sound
Espinoza, Fernando
2017-01-01
This undergraduate textbook on the physics of wave motion in optics and acoustics avoids presenting the topic abstractly in order to emphasize real-world examples. While providing the needed scientific context, Dr. Espinoza also relies on students' own experience to guide their learning. The book's exercises and labs strongly emphasize this inquiry-based approach. A strength of inquiry-based courses is that the students maintain a higher level of engagement when they are studying a topic that they have an internal motivation to know, rather than solely following the directives of a professor. "Wave Motion" takes those threads of engagement and interest and weaves them into a coherent picture of wave phenomena. It demystifies key components of life around us--in music, in technology, and indeed in everything we perceive--even for those without a strong math background, who might otherwise have trouble approaching the subject matter.
Stopping powers of energetic electrons penetrating condensed matter--theory and application
TAN Zhen-Yu; XIA Yue-Yuan
2004-01-01
In this review article, the motivation of studying inelastic energy loss for energetic electrons penetrating through matter and the corresponding technological importance have been outlined. The theoretical development and method for the calculation of stopping powers are described. The stopping power data tables for a group of polymers and bioorganic compounds are presented, and the application aspects of the stopping power data are briefly discussed.
Application of the Hilbert-Huang Transform to the Search for Gravitational Waves
Camp, Jordan B.; Cannizzo, John K.; Numata, Kenji
2007-01-01
We present the application of a novel method of time-series analysis, the Hilbert-Huang Transform, to the search for gravitational waves. This algorithm is adaptive and does not impose a basis set on the data, and thus the time-frequency decomposition it provides is not limited by time-frequency uncertainty spreading. Because of its high time-frequency resolution it has important applications to both signal detection and instrumental characterization. Applications to the data analysis of the ground and space based gravitational wave detectors, LIGO and LISA, are described.
Pulse mode operation of Love wave devices for biosensing applications.
Newton, M I; McHale, G; Martin, F; Gizeli, E; Melzak, K A
2001-12-01
In this work we present a novel pulse mode Love wave biosensor that monitors both changes in amplitude and phase. A series of concentrations of 3350 molecular weight poly(ethylene glycol) (PEG) solutions are used as a calibration sequence for the pulse mode system using a network analyzer and high frequency oscilloscope. The operation of the pulse mode system is then compared to the continuous wave network analyzer by showing a sequence of deposition and removal of a model mass layer of palmitoyl-oleoyl-sn-glycerophosphocholine (POPC) vesicles. This experimental apparatus has the potential for making many hundreds of measurements a minute and so allowing the dynamics of fast interactions to be observed.
Nonlinear dynamics of soliton gas with application to "freak waves"
Shurgalina, Ekaterina
2017-04-01
So-called "integrable soliton turbulence" attracts much attention of scientific community nowadays. We study features of soliton interactions in the following integrable systems: Korteweg - de Vries equation (KdV), modified Korteweg - de Vries equation (mKdV) and Gardner equations. The polarity of interacted solitons dramatically influences on the process of soliton interaction. Thus if solitons have the same polarity the maximum of the wave field decreases during the process of nonlinear interactions as well statistical moments (skewness and kurtosis). In this case there is no abnormally large wave formation and this scenario is possible for all considered equation. Completely different results can be obtained for a soliton gas consisted of solitons with different polarities: such interactions lead to an increase of resulting impulse and kurtosis. Tails of distribution functions can grow significantly. Abnormally large waves (freak waves) appear in such solitonic fields. Such situations are possible just in case of mKdV and Gardner equations which admit the existence of bipolar solitons. New effect of changing a defect's moving direction in soliton lattices and soliton gas is found in the present study. Manifestation of this effect is possible as the result of negative phase shift of small soliton in the moment of nonlinear interaction with large solitons. It is shown that the effect of negative velocity is the same for KdV and mKdV equations and it can be found from the kinematic assumption without applying the kinetic theory. Averaged dynamics of the "smallest" soliton (defect) in a soliton gas, consisting of solitons with random amplitudes is investigated. The averaged criterion of velocity sign change confirmed by numerical simulation is obtained.
Application of electromagnetic waves in damage detection of concrete structures
Feng, Maria Q.; De Flaviis, Franco; Kim, Yoo J.; Diaz, Rodolfo E.
2000-04-01
Jacketing technology using fiber reinforced polymer (FRP) composites is being applied for seismic retrofit of reinforced concrete (RC) columns designed and constructed under older specifications. In this study, the authors develop an electromagnetic (EM) imaging technology for detecting voids and debonding between the jacket and the column, which may significantly weaken the structural performance of the column otherwise attainable by jacketing. This technology is based on the reflection analysis of a continuous EM wave sent toward and reflected from layered FRP-adhesive-concrete medium: Poor bonding conditions including voids and debonding will generate air gaps which produce additional reflections of the EM wave. In this study, dielectric properties of various materials involved in the FRP-jacketed RC column were first measured. Second, the measured properties were used for a computer simulation of the proposed EM imaging technology. The simulation demonstrated the difficulty in detecting imperfect bonding conditions by using plane waves, as the scattering contribution from the voids and debonding is very small compared to that from the jacketed column. Third, in order to alleviate this difficulty, a special dielectric lens was designed and fabricated to focus the EM wave on the bonding interface. Furthermore, the time gating technique is used in order to reduce the noise resulting from various uncertainties associated with the jacketed columns. Finally, three concrete columns were constructed and wrapped with glass-FRP jackets with various voids and debonding condition artificially introduced in the bonding interface. Using the proposed EM imaging technology with the lens especially designed and installed, these voids and debonding condition were successfully detected.
Wave propagation in layered anisotropic media with application to composites
Nayfeh, AH
1995-01-01
Recent advances in the study of the dynamic behavior of layered materials in general, and laminated fibrous composites in particular, are presented in this book. The need to understand the microstructural behavior of such classes of materials has brought a new challenge to existing analytical tools. This book explores the fundamental question of how mechanical waves propagate and interact with layered anisotropic media. The chapters are organized in a logical sequence depending upon the complexity of the physical model and its mathematical treatment.
Mintz, Stephan; Perlmutter, Arnold; Neutrino Mass, Dark Matter and Gravitational Waves, Condensation of Atoms and Monopoles, Light-cone Quantization : Orbis Scientiae '96
1996-01-01
The International Conference, Orbis Scientiae 1996, focused on the topics: The Neutrino Mass, Light Cone Quantization, Monopole Condensation, Dark Matter, and Gravitational Waves which we have adopted as the title of these proceedings. Was there any exciting news at the conference? Maybe, it depends on who answers the question. There was an almost unanimous agreement on the overall success of the conference as was evidenced by the fact that in the after-dinner remarks by one of us (BNK) the suggestion of organizing the conference on a biannual basis was presented but not accepted: the participants wanted the continuation of the tradition to convene annually. We shall, of course, comply. The expected observation of gravitational waves will constitute the most exciting vindication of Einstein's general relativity. This subject is attracting the attention of the experimentalists and theorists alike. We hope that by the first decade of the third millennium or earlier, gravitational waves will be detected,...
A dendritic mechanism for decoding traveling waves: principles and applications to motor cortex.
Stewart Heitmann
2013-10-01
Full Text Available Traveling waves of neuronal oscillations have been observed in many cortical regions, including the motor and sensory cortex. Such waves are often modulated in a task-dependent fashion although their precise functional role remains a matter of debate. Here we conjecture that the cortex can utilize the direction and wavelength of traveling waves to encode information. We present a novel neural mechanism by which such information may be decoded by the spatial arrangement of receptors within the dendritic receptor field. In particular, we show how the density distributions of excitatory and inhibitory receptors can combine to act as a spatial filter of wave patterns. The proposed dendritic mechanism ensures that the neuron selectively responds to specific wave patterns, thus constituting a neural basis of pattern decoding. We validate this proposal in the descending motor system, where we model the large receptor fields of the pyramidal tract neurons - the principle outputs of the motor cortex - decoding motor commands encoded in the direction of traveling wave patterns in motor cortex. We use an existing model of field oscillations in motor cortex to investigate how the topology of the pyramidal cell receptor field acts to tune the cells responses to specific oscillatory wave patterns, even when those patterns are highly degraded. The model replicates key findings of the descending motor system during simple motor tasks, including variable interspike intervals and weak corticospinal coherence. By additionally showing how the nature of the wave patterns can be controlled by modulating the topology of local intra-cortical connections, we hence propose a novel integrated neuronal model of encoding and decoding motor commands.
Application of norm-conserving pseudopotentials to intense laser-matter interactions
Tong, Xiao-Min; Wachter, Georg; Sato, Shunsuke A.; Lemell, Christoph; Yabana, Kazuhiro; Burgdörfer, Joachim
2015-10-01
We investigate the applicability of norm-conserving pseudopotentials to intense laser-matter interactions by performing time-dependent density functional theory simulations with an all-electron potential and with norm-conserving pseudopotentials. We find pseudopotentials to be reliable for the simulation of above-threshold ionization over a broad range of laser intensities both for the total ionization probability and the photoelectron energy spectrum. For the simulation of high-order-harmonic generation, pseudopotentials are shown to be applicable for lower-order harmonics in the spectral range in which the one-photon recombination dipole-matrix element can be recovered by the pseudopotential calculation.
Shock wave application to rat skin induces degeneration and reinnervation of sensory nerve fibres.
Ohtori, S; Inoue, G; Mannoji, C; Saisu, T; Takahashi, K; Mitsuhashi, S; Wada, Y; Takahashi, K; Yamagata, M; Moriya, H
2001-11-23
There have been several reports on the use of extracorporeal shock waves in the treatment of pseudarthrosis, calcifying tendinitis, and tendinopathies of the elbow. However, the pathomechanism of pain relief has not been clarified. To investigate the analgesic properties of shock wave application, we analyzed whether it produces morphologic changes in cutaneous nerve fibres. In normal rat skin, the epidermis is heavily innervated by nerve fibres immunoreactive for protein gene product (PGP) 9.5 and by some fibres immunoreactive for calcitonin gene-related peptide (CGRP). There was nearly complete degeneration of epidermal nerve fibres in the shock wave-treated skin, as indicated by the loss of immunoreactivity for PGP 9.5 or CGRP. Reinnervation of the epidermis occurred 2 weeks after treatment. These data show that relief of pain after shock wave application to the skin results from rapid degeneration of the intracutaneous nerve fibres.
M. I. Baranov
2016-11-01
Full Text Available Purpose. Implementation of brief analytical review of the basic distinguished scientific achievements of the world scientists-physicists in area of discovery and study of quantum-wave nature of physical processes and phenomena flowing in the microscopic world of circumferential people matter. Methodology. Scientific methods of collection, analysis and analytical treatment of scientific and technical information in area of theoretical and experimental physics, devoted the results of researches| of quantum and physical processes flowing in nature on atomic and subatomic levels. Results. The brief scientific and technical review of the basic scientific discovery and achievements of scientists-physicists is resulted in area of structure of atom of matter, generation, radiation, distribution and absorption of physical bodies of short-wave hertzian waves, indicative on a dominating role in the microscopic financial world of positions and conformities to the law of wave (by quantum mechanics, carrying especially probabilistic character a microstructure. Originality. Systematization is executed with exposition in the short concentrated form| of the known materials| on the quantum theory (electromagnetic of caloradiance, quantum theory of atom, electronic waves, quantum theory of actinoelectricity, quantum statistics of microparticless, quantum theory of the phenomenon superfluidity of liquid helium, quantum electronics and quantum-wave nature of drift of lone electrons in the metal of explorers with an electric current. Practical value. Popularization and deepening of fundamental physical and technical knowledges for students and engineer and technical specialists in area of classic and quantum physics, extending their scientific range of interests, and also support a further scientific study by them surrounding nature and to development of scientific and technical progress in society.
This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis...
A Love Wave Reflective Delay Line with Polymer Guiding Layer for Wireless Sensor Application
Shitang He; Wen Wang
2008-01-01
This paper presents an optimal design for a Love wave reflective delay line on 41o YX LiNbO3 with a polymer guiding layer for wireless sensor applications. A theoretical model was established to describe the Love wave propagation along the larger piezoelectric substrate with polymer waveguide, and the lossy mechanism from the viscoelastic waveguide was discussed, which results in the optimal guiding layer thickness. Coupling of modes (COM) was used to determine the optimal design parameters o...
A negative refractive index metamaterial wave plate for millimetre-wave applications
Mohamed, I.; Pisano, G.; Ng, M. W.; Maffei, B.; Haynes, V.; Ozturk, F.
2012-09-01
By use of a metamaterial based on the ‘cut wire pair’ geometry, highly birefringent wave plates may be constructed by virtue of the geometry’s ability of having a negative and positive refractive index along its perpendicular axes. Past implementations have been narrow band in nature due to the reliance on producing a resonance to achieve a negative refractive index band and the steep gradient in the phase difference that results. In this paper we attempt to design and manufacture a W-band quarter wave plate embedded in polypropylene that applies the Pancharatnam method to increase the useable bandwidth. Our modelling demonstrates that a broadening of the phase difference’s bandwidth defined as the region 90° +/- 2° is possible from 0.6% (101.7 GHz - 102.3 GHz) to 7.8% (86.2 GHz - 93.1 GHz). Our experimental results show some agreement with our modelling but differ at higher frequencies.
Fauvarque, Olivier; Fusco, Thierry; Sauvage, Jean-François; Giraut, Orion
2016-01-01
In this article, we compare a set of Wave Front Sensors (WFS) based on Fourier filtering technique. In particular, this study explores the "class of pyramidal WFS" defined as the 4 faces pyramid WFS, all its recent variations (6, 8 faces, the flattened PWFS, etc.) and also some new WFSs as the flattened cone WFS or the 3 faces pyramid WFS. In the first part, we describe such a sensors class thanks to the optical parameters of the Fourier filtering mask and the modulation parameters. In the second part, we use the unified formalism to create a set of performance criteria: size of the signal on the detector, efficiency of incoming flux, sensitivity, linear range and chromaticity. In the third part, we show the influence of the previous optical and modulation parameters on these performance criteria. This exhaustive study allows to know how to optimize the sensor regarding to performance specifications. We show in particular that the number of faces has influence on the number of pixels required to do the wave f...
Canonical Acoustics and Its Application to Surface Acoustic Wave on Acoustic Metamaterials
Shen, Jian Qi
2016-08-01
In a conventional formalism of acoustics, acoustic pressure p and velocity field u are used for characterizing acoustic waves propagating inside elastic/acoustic materials. We shall treat some fundamental problems relevant to acoustic wave propagation alternatively by using canonical acoustics (a more concise and compact formalism of acoustic dynamics), in which an acoustic scalar potential and an acoustic vector potential (Φ ,V), instead of the conventional acoustic field quantities such as acoustic pressure and velocity field (p,u) for characterizing acoustic waves, have been defined as the fundamental variables. The canonical formalism of the acoustic energy-momentum tensor is derived in terms of the acoustic potentials. Both the acoustic Hamiltonian density and the acoustic Lagrangian density have been defined, and based on this formulation, the acoustic wave quantization in a fluid is also developed. Such a formalism of acoustic potentials is employed to the problem of negative-mass-density assisted surface acoustic wave that is a highly localized surface bound state (an eigenstate of the acoustic wave equations). Since such a surface acoustic wave can be strongly confined to an interface between an acoustic metamaterial (e.g., fluid-solid composite structures with a negative dynamical mass density) and an ordinary material (with a positive mass density), it will give rise to an effect of acoustic field enhancement on the acoustic interface, and would have potential applications in acoustic device design for acoustic wave control.
Kemp, B. A.
2011-06-01
A century has now passed since the origins of the Abraham-Minkowski controversy pertaining to the correct form of optical momentum in media. Experiment and theory have been applied at both the classical and quantum levels in attempt to resolve the debate. The result of these efforts is the identification of Abraham's kinetic momentum as being responsible for the overall center of mass translations of a medium and Minkowski's canonical or wave momentum as being responsible for translations within or with respect to a medium. In spite of the recent theoretical developments, much confusion still exists regarding the appropriate theory required to predict experimental outcomes and to develop new applications. In this paper, the resolution of the longstanding Abraham-Minkowski controversy is reviewed. The resolution is presented using classical electromagnetic theory and logical interpretation of experiments disseminated over the previous century. Emphasis is placed on applied physics applications: modeling optical manipulation of cells and particles. Although the basic interpretation of optical momentum has been resolved, there is still some uncertainly regarding the complete form of the momentum continuity equation describing electromagnetics. Thus, while a complete picture of electrodynamics has still yet to be fully interpreted, this correspondence should help clarify the state-of-the-art view.
Guided wave photonics fundamentals and applications with Matlab
Binh, Le Nguyen
2012-01-01
IntroductionHistorical Overview of Integrated Optics and PhotonicsWhy Analysis of Optical Guided-wave Devices?Principal ObjectivesChapters OverviewSingle Mode Planar Optical WaveguidesFormation of Planar Single Mode Waveguide ProblemsApproximate Analytical Methods of SolutionAPPENDIX A: Maxwell Equations in Dielectric MediaAPPENDIX B: Exact Analysis of Clad-linear Optical WaveguidesAPPENDIX C: Wentzel-Kramers-Brilluoin Method, Turning Points and Connection FormulaeAPPENDIX D: Design and Simulation of Planar Optical Waveguides3D Integrated Optical WaveguidesMarcatili's Method| Effective Index M
Millimeter-Wave Wireless Power Transfer Technology for Space Applications
Chattopadhyay, Goutam; Manohara, Harish; Mojarradi, Mohammad M.; Vo, Tuan A.; Mojarradi, Hadi; Bae, Sam Y.; Marzwell, Neville
2008-01-01
In this paper we present a new compact, scalable, and low cost technology for efficient receiving of power using RF waves at 94 GHz. This technology employs a highly innovative array of slot antennas that is integrated on substrate composed of gold (Au), silicon (Si), and silicon dioxide (SiO2) layers. The length of the slots and spacing between them are optimized for a highly efficient beam through a 3-D electromagnetic simulation process. Antenna simulation results shows a good beam profile with very low side lobe levels and better than 93% antenna efficiency.
Inertial quantum sensors using light and matter
Barrett, B; Bouyer, P
2016-01-01
The past few decades have seen dramatic progress in our ability to manipulate and coherently control matter-waves. Although the duality between particles and waves has been well tested since de Broglie introduced the matter-wave analog of the optical wavelength in 1924, manipulating atoms with a level of coherence that enables one to use these properties for precision measurements has only become possible with our ability to produce atomic samples exhibiting temperatures of only a few millionths of a degree above absolute zero. Since the initial experiments a few decades ago, the field of atom optics has developed in many ways, with both fundamental and applied significance. The exquisite control of matter waves offers the prospect of a new generation of force sensors exhibiting unprecedented sensitivity and accuracy, for applications from navigation and geophysics to tests of general relativity. Thanks to the latest developments in this field, the first commercial products using this quantum technology are n...
Acoustics waves and oscillations
Sen, S.N.
2013-01-01
Parameters of acoustics presented in a logical and lucid style Physical principles discussed with mathematical formulations Importance of ultrasonic waves highlighted Dispersion of ultrasonic waves in viscous liquids explained This book presents the theory of waves and oscillations and various applications of acoustics in a logical and simple form. The physical principles have been explained with necessary mathematical formulation and supported by experimental layout wherever possible. Incorporating the classical view point all aspects of acoustic waves and oscillations have been discussed together with detailed elaboration of modern technological applications of sound. A separate chapter on ultrasonics emphasizes the importance of this branch of science in fundamental and applied research. In this edition a new chapter ''Hypersonic Velocity in Viscous Liquids as revealed from Brillouin Spectra'' has been added. The book is expected to present to its readers a comprehensive presentation of the subject matter...
Goffin, Angélique; Guérin, Sabrina; Rocher, Vincent; Varrault, Gilles
2016-04-01
Dissolved organic matter (DOM) influences wastewater treatment plants efficiency (WTTP): variations in its quality and quantity can induce a foaming phenomenon and a fouling event inside biofiltration processes. Moreover, in order to manage denitrification step (control and optimization of the nitrate recirculation), it is important to be able to estimate biodegradable organic matter quantity before biological treatment. But the current methods used to characterize organic matter quality, like biological oxygen demand are laborious, time consuming and sometimes not applicable to directly monitor organic matter in situ. In the context of MOCOPEE research program (www.mocopee.com), this study aims to assess the use of optical techniques, such as UV-Visible absorbance and more specifically fluorescence spectroscopy in order to monitor and to optimize process efficiency in WWTP. Fluorescence excitation-emission matrix (EEM) spectroscopy was employed to prospect the possibility of using this technology online and in real time to characterize dissolved organic matter in different effluents of the WWTP Seine Centre (240,000 m3/day) in Paris, France. 35 sewage water influent samples were collected on 10 days at different hours. Data treatment were performed by two methods: peak picking and parallel factor analysis (PARAFAC). An evolution of DOM quality (position of excitation - emission peaks) and quantity (intensity of fluorescence) was observed between the different treatment steps (influent, primary treatment, biological treatment, effluent). Correlations were found between fluorescence indicators and different water quality key parameters in the sewage influents. We developed different multivariate linear regression models in order to predict a variety of water quality parameters by fluorescence intensity at specific excitation-emission wavelengths. For example dissolved biological oxygen demand (r2=0,900; p<0,0001) and ammonium concentration (r2=0,898; p<0
Pietrow, M
2016-01-01
Considerable similarity between positronium atom and an exciton in a quantum dot is indicated. Following this, we apply the calculation regime from the theory of excitons to describe some aspects of formation of a positronium in matter. We consider the possibility of photonic deexcitation during Ps formation and show the way of calculation of its probability. The photonic transitions speculated here, if detected, allows improving experimental studies of solid matter with positron techniques.
Wu Xuebang
2015-09-01
Full Text Available The general trend in soft matter is to study systems of increasing complexity covering a wide range in time and frequency. Mechanical spectroscopy is a powerful tool for understanding the structure and relaxation dynamics of these materials over a large temperature range and frequency scale. In this work, we collect a few recent applications using low-frequency mechanical spectroscopy for elucidating the structural changes and relaxation dynamics in soft matter, largely based on the author’s group. We illustrate the potential of mechanical spectroscopy with three kinds of soft materials: colloids, polymers and granular systems. Examples include structural changes in colloids, segmental relaxations in amorphous polymers, and resonant dissipation of grain chains in three-dimensional media. The present work shows that mechanical spectroscopy has been applied as a necessary and complementary tool to study the dynamics of such complex systems.
Application of a high-performance damping metal to gravitational wave detectors
Mio, N; Moriwaki, S
2002-01-01
We have investigated applications of a high-performance damping metal, called M2052, which is a manganese-based alloy containing copper, nickel and iron. Using an all-metal prototype of a vibration isolation system, we have tested the property of M2052. As its actual application to a gravitational wave detector, we have used M2052 in the damping system of a suspended optics in TAMA300, which is a 300 m long interferometric gravitational wave detector built at the Mitaka campus of the National Astronomical Observatory in Japan. The results of the experiments are reported.
On a class of nonlocal wave equations from applications
Beyer, Horst Reinhard; Aksoylu, Burak; Celiker, Fatih
2016-06-01
We study equations from the area of peridynamics, which is a nonlocal extension of elasticity. The governing equations form a system of nonlocal wave equations. We take a novel approach by applying operator theory methods in a systematic way. On the unbounded domain ℝn, we present three main results. As main result 1, we find that the governing operator is a bounded function of the governing operator of classical elasticity. As main result 2, a consequence of main result 1, we prove that the peridynamic solutions strongly converge to the classical solutions by utilizing, for the first time, strong resolvent convergence. In addition, main result 1 allows us to incorporate local boundary conditions, in particular, into peridynamics. This avenue of research is developed in companion papers, providing a remedy for boundary effects. As main result 3, employing spherical Bessel functions, we give a new practical series representation of the solution which allows straightforward numerical treatment with symbolic computation.
Structural Reliability of Plain Bearings for Wave Energy Converter Applications
Simon Ambühl
2016-02-01
Full Text Available The levelized cost of energy (LCOE from wave energy converters (WECs needs to be decreased in order to be able to become competitive with other renewable electricity sources. Probabilistic reliability methods can be used to optimize the structure of WECs. Optimization is often performed for critical structural components, like welded details, bolts or bearings. This paper considers reliability studies with a focus on plain bearings available from stock for the Wavestar device, which exists at the prototype level. The Wavestar device is a point absorber WEC. The plan is to mount a new power take-off (PTO system consisting of a discrete displacement cylinder (DDC, which will allow different hydraulic cycles to operate at constant pressure levels. This setup increases the conversion efficiency, as well as decouples the electricity production from the pressure variations within the hydraulic cycle when waves are passing. The new PTO system leads to different load characteristics at the floater itself compared to the actual setup where the turbine/generator is directly coupled to the fluctuating hydraulic pressure within the PTO system. This paper calculates the structural reliability of the different available plain bearings planned to be mounted at the new PTO system based on a probabilistic approach, and the paper gives suggestions for fulfilling the minimal target reliability levels. The considered failure mode in this paper is the brittle fatigue failure of plain bearings. The performed sensitivity analysis shows that parameters defining the initial crack size have a big impact on the resulting reliability of the plain bearing.
Effectiveness of radio waves application in modern general dental procedures: An update.
Qureshi, Arslan; Kellesarian, Sergio Varela; Pikos, Michael A; Javed, Fawad; Romanos, Georgios E
2017-01-01
The purpose of the present study was to review indexed literature and provide an update on the effectiveness of high-frequency radio waves (HRW) application in modern general dentistry procedures. Indexed databases were searched to identify articles that assessed the efficacy of radio waves in dental procedures. Radiosurgery is a refined form of electrosurgery that uses waves of electrons at a radiofrequency ranging between 2 and 4 MHz. Radio waves have also been reported to cause much less thermal damage to peripheral tissues compared with electrosurgery or carbon dioxide laser-assisted surgery. Formation of reparative dentin in direct pulp capping procedures is also significantly higher when HRW are used to achieve hemostasis in teeth with minimally exposed dental pulps compared with traditional techniques for achieving hemostasis. A few case reports have reported that radiosurgery is useful for procedures such as gingivectomy and gingivoplasty, stage-two surgery for implant exposure, operculectomy, oral biopsy, and frenectomy. Radiosurgery is a relatively modern therapeutic methodology for the treatment of trigeminal neuralgia; however, its long-term efficacy is unclear. Radio waves can also be used for periodontal procedures, such as gingivectomies, coronal flap advancement, harvesting palatal grafts for periodontal soft tissue grafting, and crown lengthening. Although there are a limited number of studies in indexed literature regarding the efficacy of radio waves in modern dentistry, the available evidence shows that use of radio waves is a modernization in clinical dentistry that might be a contemporary substitute for traditional clinical dental procedures.
Compressive sensing of full wave field data for structural health monitoring applications.
Di Ianni, Tommaso; De Marchi, Luca; Perelli, Alessandro; Marzani, Alessandro
2015-07-01
Numerous nondestructive evaluations and structural health monitoring approaches based on guide waves rely on analysis of wave fields recorded through scanning laser Doppler vibrometers (SLDVs) or ultrasonic scanners. The informative content which can be extracted from these inspections is relevant; however, the acquisition process is generally time-consuming, posing a limit in the applicability of such approaches. To reduce the acquisition time, we use a random sampling scheme based on compressive sensing (CS) to minimize the number of points at which the field is measured. The CS reconstruction performance is mostly influenced by the choice of a proper decomposition basis to exploit the sparsity of the acquired signal. Here, different bases have been tested to recover the guided waves wave field acquired on both an aluminum and a composite plate. Experimental results show that the proposed approach allows a reduction of the measurement locations required for accurate signal recovery to less than 34% of the original sampling grid.
Review on Millimeter Wave Antennas- Potential Candidate for 5G Enabled Applications
M. A. Matin
2016-12-01
Full Text Available The millimeter wave (mmWave band is considered as the potential candidate for high speed communication services in 5G networks due to its huge bandwidth. Moreover, mmWave frequencies lead to miniaturization of RF front end including antennas. In this article, we provide an overview of recent research achievements of millimeter-wave antenna design along with the design considerations for compact antennas and antennas in package/on chip, mostly in the 60 GHz band is described along with their inherent benefits and challenges. A comparative analysis of various designs is also presented. The antennas with wide bandwidth, high-gain, compact size and low profile with easiness of integration in-package or on-chip with other components are required for 5G enabled applications.
A CMB-based approach to mapping gravitational-wave backgrounds: application to pulsar timing arrays
Gair, Jonathan R; Taylor, Stephen; Mingarelli, Chiara M F
2014-01-01
We describe an alternative approach to the analysis of gravitational-wave backgrounds, based on the formalism used to characterise the polarisation of the cosmic microwave background. An arbitrary background can be decomposed into modes whose angular dependence on the sky is given by gradients and curls of spherical harmonics. We derive the pulsar timing overlap reduction function for individual modes, which are given by simple combinations of spherical harmonics evaluated at the pulsar locations. We show how these can be used to recover the components of an arbitrary background, giving explicit results for both isotropic and anisotropic uncorrelated backgrounds. We also find that the response of a pulsar timing array to curl modes is identically zero, so half of the gravitational-wave sky will never be observed using pulsar timing, no matter how many pulsars are included in the array. An isotropic uncorrelated background can be accurately represented using only three components, and so a search of this type ...
Damage imaging using Lamb waves for SHM applications
Stepinski, Tadeusz, E-mail: tstepin@agh.edu.pl; Ambroziński, Łukasz, E-mail: tstepin@agh.edu.pl; Uhl, Tadeusz, E-mail: tstepin@agh.edu.pl [AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland)
2015-03-31
2-D ultrasonic arrays, due to their beam-steering capability and all azimuth angle coverage are a very promising tool for the inspection of plate-like structures using Lamb waves (LW). Contrary to the classical linear phased arrays (PAs) the 2D arrays enable unequivocal defect localization and they are even capable of mode selectivity of the received LWs . Recently, it has been shown that multistatic synthetic focusing (SF) algorithms applied for 2D arrays are much more effective than the classical phase array mode commonly used in NDT. The multistatic SF assumes multiple transmissions of elements in a transmitting aperture and off-line processing of the data acquired by a receiving aperture. In the simplest implementation of the technique, only a single multiplexed input and a number of output channels are required, which results in significant hardware simplification compared with the PA systems. On the one hand implementation of the multistatic SF to 2D arrays creates additional degrees of freedom during the design of the array topology, which complicates the array design process. On the other hand, it enables designing sparse arrays with performance similar to that of the fully populated dense arrays. In this paper we present a general systematic approach to the design and optimization of imaging systems based on the 2D array operating in the multistatic mode. We start from presenting principles of the SF schemes applied to LW imaging. Then, we outline the coarray concept and demonstrate how it can be used for reducing number of elements of the 2D arrays. Finally, efficient tools for the investigation and experimental verification of the designed 2D array prototypes are presented. The first step in the investigation is theoretical evaluation performed using frequency-dependent structure transfer function (STF), which enables approximate simulation of an array excited with a tone-burst in a dispersive medium. Finally, we show how scanning laser vibrometer
Damage imaging using Lamb waves for SHM applications
Stepinski, Tadeusz; Ambroziński, Łukasz; Uhl, Tadeusz
2015-03-01
2-D ultrasonic arrays, due to their beam-steering capability and all azimuth angle coverage are a very promising tool for the inspection of plate-like structures using Lamb waves (LW). Contrary to the classical linear phased arrays (PAs) the 2D arrays enable unequivocal defect localization and they are even capable of mode selectivity of the received LWs . Recently, it has been shown that multistatic synthetic focusing (SF) algorithms applied for 2D arrays are much more effective than the classical phase array mode commonly used in NDT. The multistatic SF assumes multiple transmissions of elements in a transmitting aperture and off-line processing of the data acquired by a receiving aperture. In the simplest implementation of the technique, only a single multiplexed input and a number of output channels are required, which results in significant hardware simplification compared with the PA systems. On the one hand implementation of the multistatic SF to 2D arrays creates additional degrees of freedom during the design of the array topology, which complicates the array design process. On the other hand, it enables designing sparse arrays with performance similar to that of the fully populated dense arrays. In this paper we present a general systematic approach to the design and optimization of imaging systems based on the 2D array operating in the multistatic mode. We start from presenting principles of the SF schemes applied to LW imaging. Then, we outline the coarray concept and demonstrate how it can be used for reducing number of elements of the 2D arrays. Finally, efficient tools for the investigation and experimental verification of the designed 2D array prototypes are presented. The first step in the investigation is theoretical evaluation performed using frequency-dependent structure transfer function (STF), which enables approximate simulation of an array excited with a tone-burst in a dispersive medium. Finally, we show how scanning laser vibrometer
Future applications of millimeter waves for space communications
Rusch, Roger J.
1996-12-01
The past 30 years have witnessed the introduction and phenomenal improvement of digital communications services. Several characteristics emerge when looking at the trends. First, capacity and capability of communications networks are growing rapidly. Next, local and personal access to digital services is expanding. Finally, ordinary 4 kHz analog voice lines are now providing 28.8 kbps digital services in the home. Only 15 years ago, this data rate was 300 bps, a growth factor of 96 in 15 years or 36 percent per year. In addition, clever data compression techniques have reduced the data rates required for speech and video, and we now have the ability to provide video conferencing on computers using existing terrestrial networks. As the world makes greater use of wireless communications, hundreds of satellites are orbiting in space to provide fixed and mobile services. Because of the large number of satellites, the geostationary orbit is heavily used. More sophisticated satellites could be designed, but a simpler solution is to move to higher frequencies offered by millimeter wave bands. Dozens of US companies are currently developing systems that will provide high data services to the world.
Samiksha, S.V.; Polnikov, V.G.; Vethamony, P.; Rashmi, R.; Pogarskii, F.; Sudheesh, K.
for the model comparison. Based on the error estimates of significant wave heights and spectral wave energy, improvement achieved in wave prediction using ModWAM is demonstrated. We find that the ModWAM improved the accuracy of significant wave height prediction...
Witten, Matthew
1983-01-01
Hyperbolic Partial Differential Equations, Volume 1: Population, Reactors, Tides and Waves: Theory and Applications covers three general areas of hyperbolic partial differential equation applications. These areas include problems related to the McKendrick/Von Foerster population equations, other hyperbolic form equations, and the numerical solution.This text is composed of 15 chapters and begins with surveys of age specific population interactions, populations models of diffusion, nonlinear age dependent population growth with harvesting, local and global stability for the nonlinear renewal eq
Wave model and self-organization theory of C-space: application in the ergonomics and design
Kovalev, Y. N.; National Aviation University, Ukraine
2012-01-01
Axiomatic wave model and self-organization theory of s– spaceand their application for modeling and optimization of human–machine systems and person–dwelling–environment systems are considered. Axiomatic wave model and self-organization theory of s– spaceand their application for modeling and optimization of human–machine systems and person–dwelling–environment systems are considered.
Michael-Kordatou, I; Michael, C; Duan, X; He, X; Dionysiou, D D; Mills, M A; Fatta-Kassinos, D
2015-06-15
Wastewater reuse is currently considered globally as the most critical element of sustainable water management. The dissolved effluent organic matter (dEfOM) present in biologically treated urban wastewater, consists of a heterogeneous mixture of refractory organic compounds with diverse structures and varying origin, including dissolved natural organic matter, soluble microbial products, endocrine disrupting compounds, pharmaceuticals and personal care products residues, disinfection by-products, metabolites/transformation products and others, which can reach the aquatic environment through discharge and reuse applications. dEfOM constitutes the major fraction of the effluent organic matter (EfOM) and due to its chemical complexity, it is necessary to utilize a battery of complementary techniques to adequately describe its structural and functional character. dEfOM has been shown to exhibit contrasting effects towards various aquatic organisms. It decreases metal uptake, thus potentially reducing their bioavailability to exposed organisms. On the other hand, dEfOM can be adsorbed on cell membranes inducing toxic effects. This review paper evaluates the performance of various advanced treatment processes (i.e., membrane filtration and separation processes, activated carbon adsorption, ion-exchange resin process, and advanced chemical oxidation processes) in removing dEfOM from wastewater effluents. In general, the literature findings reveal that dEfOM removal by advanced treatment processes depends on the type and the amount of organic compounds present in the aqueous matrix, as well as the operational parameters and the removal mechanisms taking place during the application of each treatment technology. Copyright © 2015 Elsevier Ltd. All rights reserved.
Application of the Most Likely Extreme Response Method for Wave Energy Converters: Preprint
Quon, Eliot; Platt, Andrew; Yu, Yi-Hsiang; Lawson, Michael
2016-07-01
Extreme loads are often a key cost driver for wave energy converters (WECs). As an alternative to exhaustive Monte Carlo or long-term simulations, the most likely extreme response (MLER) method allows mid- and high-fidelity simulations to be used more efficiently in evaluating WEC response to events at the edges of the design envelope, and is therefore applicable to system design analysis. The study discussed in this paper applies the MLER method to investigate the maximum heave, pitch, and surge force of a point absorber WEC. Most likely extreme waves were obtained from a set of wave statistics data based on spectral analysis and the response amplitude operators (RAOs) of the floating body; the RAOs were computed from a simple radiation-and-diffraction-theory-based numerical model. A weakly nonlinear numerical method and a computational fluid dynamics (CFD) method were then applied to compute the short-term response to the MLER wave. Effects of nonlinear wave and floating body interaction on the WEC under the anticipated 100-year waves were examined by comparing the results from the linearly superimposed RAOs, the weakly nonlinear model, and CFD simulations. Overall, the MLER method was successfully applied. In particular, when coupled to a high-fidelity CFD analysis, the nonlinear fluid dynamics can be readily captured.
Study of Rotating-Wave Electromagnetic Modes for Applications in Space Exploration
Velazco, J. E.
2016-08-01
Rotating waves are circularly polarized electromagnetic wave fields that behave like traveling waves but have discrete resonant frequencies of standing waves. In JPL's Communications Ground Systems Section (333), we are making use of this peculiar type of electromagnetic modes to develop a new generation of devices and instruments for direct applications in space exploration. In this article, we present a straightforward analysis about the phase velocity of these wave modes. A derivation is presented for the azimuthal phase velocity of transverse magnetic rotating modes inside cylindrical cavity resonators. Computer simulations and experimental measurements are also presented that corroborate the theory developed. It is shown that the phase velocity of rotating waves inside cavity resonators increases with radial position within the cavity and decreases when employing higher-order operating modes. The exotic features of rotating modes, once better understood, have the potential to enable the implementation of a plethora of new devices that range from amplifiers and frequency multipliers to electron accelerators and ion thrusters.
Application of the Most Likely Extreme Response Method for Wave Energy Converters
Quon, Eliot; Platt, Andrew; Yu, Yi-Hsiang; Lawson, Michael
2016-06-24
Extreme loads are often a key cost driver for wave energy converters (WECs). As an alternative to exhaustive Monte Carlo or long-term simulations, the most likely extreme response (MLER) method allows mid- and high-fidelity simulations to be used more efficiently in evaluating WEC response to events at the edges of the design envelope, and is therefore applicable to system design analysis. The study discussed in this paper applies the MLER method to investigate the maximum heave, pitch, and surge force of a point absorber WEC. Most likely extreme waves were obtained from a set of wave statistics data based on spectral analysis and the response amplitude operators (RAOs) of the floating body; the RAOs were computed from a simple radiation-and-diffraction-theory-based numerical model. A weakly nonlinear numerical method and a computational fluid dynamics (CFD) method were then applied to compute the short-term response to the MLER wave. Effects of nonlinear wave and floating body interaction on the WEC under the anticipated 100-year waves were examined by comparing the results from the linearly superimposed RAOs, the weakly nonlinear model, and CFD simulations. Overall, the MLER method was successfully applied. In particular, when coupled to a high-fidelity CFD analysis, the nonlinear fluid dynamics can be readily captured.
Application of the SPH method to solitary wave impact on an offshore platform
Pan, K.; IJzermans, R. H. A.; Jones, B. D.; Thyagarajan, A.; van Beest, B. W. H.; Williams, J. R.
2016-04-01
This paper investigates the interaction between large waves and floating offshore structures. Here, the fluid-structure interaction is considered using the weakly compressible smoothed particle hydrodynamics (SPH) method. To ensure the applicability of this method, we validate its prediction for fluid forces and rigid-body motion against two sets of experimental data. These are impact due to dam break, and wave induced motion of a floating cube. For the dam break problem, the SPH method is used to predict impact forces on a rectangular column located downstream. In the second case of a floating cube, the SPH method simulates the motion of a buoyant cube under the action of induced waves, where a wall placed upstream of the cube is displaced sinusoidally to induce waves. In both cases, the SPH framework implemented is able to accurately reproduce the experimental results. Following validation, we apply this framework to simulation of a toy model of a tension-leg platform upon impact of a large solitary wave. This analysis shows that the platform may be pulled into the water by stretched tension legs, where the extension of the tension legs also governs the rotational behavior of the platform. The result also indicates that a tension-leg platform is very unlikely to topple over during the arrival of an extreme wave.
Exact Spherical Wave Solutions to Maxwell's Equations with Applications
Silvestri, Guy G.
Electromagnetic radiation from bounded sources represent an important class of physical problems that can be solved for exactly. However, available texts on this subject almost always resort to approximate solution techniques that not only obscure the essential features of the problem but also restrict application to limited ranges of observation. This dissertation presents exact solutions for this important class of problems and demonstrates how these solutions can be applied to situations of genuine physical interest, in particular, the design of device structures with prespecified emission characteristics. The strategy employed is to solve Maxwell's equations in the spherical coordinate system. In this system, fundamental parameters such as electric and magnetic multipole moments fall out quite naturally. Expressions for radiated power, force, and torque assume especially illuminating and simple forms when expressed in terms of these multipole moments. All solutions are derived ab initio using first-principles arguments exclusively. Two operator-equations that receive particularly detailed treatment are the vector Helmholtz equation for the time-independent potential vec a and the "covariant divergence" equation for the energy-momentum-stress tensor T^{mu nu}. An application of classical formulas, as modified by the requirements of statistical mechanics, to the case of heated blackbodies leads to inquiries into the foundations of quantum mechanics and their relation to classical field theory. An application of formulas to various emission structures (spherically-shaped antennas, surface diffraction gratings, collimated beams) provides a basis upon which to characterize these structures in an exact sense, and, ultimately, to elicit clues as to their optimum design.
Electronically steerable millimeter wave antenna techniques for space shuttle applications
Kummer, W. H.
1975-01-01
A large multi-function antenna aperture and related components are described which will perform electronic steering of one or more beams for two of the three applications envisioned: (1) communications, (2) radar, and (3) radiometry. The array consists of a 6-meter folded antenna that fits into two pallets. The communications frequencies are 20 and 30 GHz, while the radar is to operate at 13.9 GHz. Weight, prime power, and volumes are given parametrically; antenna designs, electronics configurations, and mechanical design were studied.
Compact Receiver Front Ends for Submillimeter-Wave Applications
Mehdi, Imran; Chattopadhyay, Goutam; Schlecht, Erich T.; Lin, Robert H.; Sin, Seth; Peralta, Alejandro; Lee, Choonsup; Gill, John J.; Gulkis, Samuel; Thomas, Bertrand C.
2012-01-01
The current generation of submillimeter-wave instruments is relatively mass and power-hungry. The receiver front ends (RFEs) of a submillimeter instrument form the heart of the instrument, and any mass reduction achieved in this subsystem is propagated through the instrument. In the current implementation, the RFE consists of different blocks for the mixer and LO circuits. The motivation for this work is to reduce the mass of the RFE by integrating the mixer and LO circuits in one waveguide block. The mixer and its associated LO chips will all be packaged in a single waveguide package. This will reduce the mass of the RFE and also provide a number of other advantages. By bringing the mixer and LO circuits close together, losses in the waveguide will be reduced. Moreover, the compact nature of the block will allow for better thermal control of the block, which is important in order to reduce gain fluctuations. A single waveguide block with a 600- GHz RFE functionality (based on a subharmonically pumped Schottky diode pair) has been demonstrated. The block is about 3x3x3 cubic centimeters. The block combines the mixer and multiplier chip in a single package. 3D electromagnetic simulations were carried out to design the waveguide circuit around the mixer and multiplier chip. The circuit is optimized to provide maximum output power and maximum bandwidth. An integrated submillimeter front end featuring a 520-600-GHz sub-harmonic mixer and a 260-300-GHz frequency tripler in a single cavity was tested. Both devices used GaAs MMIC membrane planar Schottky diode technology. The sub-harmonic mixer/tripler circuit has been tested using conventional metal-machined blocks. Measurement results on the metal block give best DSB (double sideband) mixer noise temperature of 2,360 K and conversion losses of 7.7 dB at 520 GHz. The LO input power required to pump the integrated tripler/sub-harmonic mixer is between 30 and 50 mW.
Extreme wave analysis in the space-time domain: from observations to applications
Barbariol, Francesco; Alves, Jose-Henrique; Benetazzo, Alvise; Bergamasco, Filippo; Carniel, Sandro; Chao, Yung Y.; Chawla, Arun; Ricchi, Antonio; Sclavo, Mauro
2016-04-01
The occurrence of extreme waves is one of the most dangerous marine hazards and one of the most challenging sea surface phenomena to be understood. Many severe accidents and casualties at sea are ascribed to the occurrence of abnormally high waves. Despite significant efforts to investigate their occurrence, up to now research has not yet provided exhaustive experimental and theoretical frameworks able to fully explain the development of extremely large waves (i.e. waves that are outlier from standard wave statistics). Recently, relying on the stereo-photogrammetric instrumentation known as "Wave Acquisition Stereo System", it was observed that the number of waves that can be labeled as "freak" increases significantly if the domain of observation is extended from the time (i.e. the classical point time series), to the space-time (i.e. a time sequence of sea surface snapshots covering an area). The empirical statistics of such extremely high waves gathered during a sea state over an area, outlying standard linear and nonlinear extreme value models, have been found in fair agreement with a statistical model accounting for the probability of a maximum crest height occurring in a space-time domain of given size. This model, developed by Fedele (2012) and extended to second order nonlinear waves by Benetazzo et al (2015), relies upon the Euler Characteristics approach of Adler and Taylor (2007), and upon the knowledge of kinematic and geometric properties of the sea state that can be obtained from the directional spectrum of the sea surface. Therefore, new efforts have been put on applying this approach to provide an interpretation of the occurrence of extreme crest heights in sea states, observed via stereo photography. Results have allowed the development of applications in ocean engineering and weather forecasting. In the former, the statistical model of Fedele has been used to investigate the role of metocean forcings on the space-time extremes of sea states. To
Lamb, George L
1995-01-01
INTRODUCTORY APPLICATIONS OF PARTIAL DIFFERENTIAL EQUATIONS. With Emphasis on Wave Propagation and Diffusion. This is the ideal text for students and professionals who have some familiarity with partial differential equations, and who now wish to consolidate and expand their knowledge. Unlike most other texts on this topic, it interweaves prior knowledge of mathematics and physics, especially heat conduction and wave motion, into a presentation that demonstrates their interdependence. The result is a superb teaching text that reinforces the reader's understanding of both mathematics and physic
Larsén, Xiaoli Guo; Kalogeri, Christina; Galanis, George
2015-01-01
Rev, which is located in the North Sea, west of Denmark. The post-processing targets at correcting the modeled time series of the significant wave height, in order to match the statistics of the corresponding measurements, including not only the conventional parameters such as the mean and standard...... as a characteristic index of extreme wave conditions. The results from the proposed methodology seem to be in a good agreement with the measurements at both the relatively deep, open water and the shallow, coastal water sites, providing a potentially useful tool for offshore renewable energy applications. © 2015...
Gray, Alexander; Kronast, Florian; Papp, Christian; Yang, See-Hun; Cramm, Stefan; Krug, Ingo P.; Salmassi, Farhad; Gullikson, Eric M.; Hilken, Dawn L.; Anderson, Erik H.; Fischer, Peter; Durr, Hermann A.; Schneider, Claus M.; Fadley, Charles S.
2010-10-29
We demonstrate the addition of depth resolution to the usual two-dimensional images in photoelectron emission microscopy (PEEM), with application to a square array of circular magnetic Co microdots. The method is based on excitation with soft x-ray standing-waves generated by Bragg reflection from a multilayer mirror substrate. Standing wave is moved vertically through sample simply by varying the photon energy around the Bragg condition. Depth-resolved PEEM images were obtained for all of the observed elements. Photoemission intensities as functions of photon energy were compared to x-ray optical calculations in order to quantitatively derive the depth-resolved film structure of the sample.
Kan'an, A. M.; Puri, A.
1994-01-01
The transmission matrix approach is generalized to calculate the transmission probability of obliquely incident electrons through arbitrary shape potential profiles. Transmission probability is obtained as a function of the electron energy, the angle of incidence, and the applied voltage across the structure. Applications to electron waveguide and quantum resonant tunneling are outlined. Numerical results are presented for angle dependent resonant tunneling through biased multibarrier GaAs-AlxGa1-xAs heterostructures. As a consequence, various novel quantum devices, i.e., high speed switch, tunable electron wave filter, and electron wave beam splitter are proposed.
The Bloch wave operator: generalizations and applications: II. The time-dependent case
Jolicard, Georges [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France); Killingbeck, John P [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France); Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom)
2003-10-10
Part II of the review shows how the stationary Bloch wave operator of part I can be suitably modified to give a time-dependent wave operator. This operator makes it possible to use a relatively small active space in order to describe the dynamical processes which occur in quantum mechanical systems which have a time-dependent Hamiltonian. A close study is made of the links between the time-dependent and time-independent wave operators at the adiabatic limit; the analysis clarifies the way in which the wave operator formalism allows the time evolution of a system or a wave packet to be described in terms of a fast evolution inside the active space together with weak transitions out of this space which can be treated by perturbation methods. Two alternative wave operator equations of motion are derived and analysed. The first one is a non-linear differential equation in the usual Hilbert space; the second one is a differential equation in an extended Hilbert space with an extra time variable added and becomes equivalent to the usual Bloch equation when the Floquet Hamiltonian is taken in place of the ordinary Hamiltonian. A study is made of the close relationships between the time-dependent wave operator formalism, the Floquet theory and the (t, t') theory. Some original methods of solution of the two forms of wave operator equation are proposed and lead to new techniques of integration for the time-dependent Schroedinger equation (e.g., the generalized Green equation procedure). Mixed procedures involving both the time-independent and time-dependent wave operators are shown to be applicable to the internal eigenstate problem for large complex matrices. A detailed account is given of the description of inelastic and photoreactive processes by means of the time-dependent wave operator formalism, with particular attention to laser-molecule interactions. The emphasis is on projection operator techniques, with special attention being given to the method of selection
Propagation of Nonlinear Waves in Waveguides and Application to Nondestructive Stress Measurement
Nucera, Claudio
Propagation of nonlinear waves in waveguides is a field that has received an ever increasing interest in the last few decades. Nonlinear guided waves are excellent candidates for interrogating long waveguide like structures because they combine high sensitivity to structural conditions, typical of nonlinear parameters, with large inspection ranges, characteristic of wave propagation in bounded media. The primary topic of this dissertation is the analysis of ultrasonic waves, including ultrasonic guided waves, propagating in their nonlinear regime and their application to structural health monitoring problems, particularly the measurement of thermal stress in Continuous Welded Rail (CWR). Following an overview of basic physical principles generating nonlinearities in ultrasonic wave propagation, the case of higher-harmonic generation in multi-mode and dispersive guided waves is examined in more detail. A numerical framework is developed in order to predict favorable higher-order generation conditions (i.e. specific guided modes and frequencies) for waveguides of arbitrary cross-sections. This model is applied to various benchmark cases of complex structures. The nonlinear wave propagation model is then applied to the case of a constrained railroad track (CWR) subjected to thermal variations. This study is a direct response to the key need within the railroad transportation community to develop a technique able to measure thermal stresses in CWR, or determine the rail temperature corresponding to a null thermal stress (Neutral Temperature -- NT). The numerical simulation phase concludes with a numerical study performed using ABAQUS commercial finite element package. These analyses were crucial in predicting the evolution of the nonlinear parameter beta with thermal stress level acting in the rail. A novel physical model, based on interatomic potential, was developed to explain the origin of nonlinear wave propagation under constrained thermal expansion. In fact
A first course in vibrations and waves
Samiullah, Mohammad
2015-01-01
This book builds on introductory physics and emphasizes understanding of vibratory motion and waves based on first principles. The book is divided into three parts. Part I contains a preliminary chapter that serves as a review of relevant ideas of mechanics and complex numbers. Part II is devoted to a detailed discussion of vibrations of mechanical systems. This part covers a simple harmonic oscillator, coupled oscillators, normal coordinates, beaded string, continuous string, standing waves, and Fourier series. Part II ends with a presentation of stationary solutions of driven finite systems. Part III is concerned with waves. Here, the emphasis is on the discussion of common aspects of all types of waves. The applications to sound, electromagnetic, and matter waves are illustrated. The book also includes examples from water waves and electromagnetic waves on a transmission line. The emphasis of the book is to bring out the similarities among various types of waves. The book includes treatment of reflection a...
Minardi, S.; Harieni, S.; Anasrullah, A.; Purwanto, H.
2017-04-01
Objective of this study were to elucidate effects of organic matters and P fertilizer application on soil fertility status, nutrient uptake and maize yield in the Andisol. This experiment consisted of two factors. The first factor comprised of four levels of organic matters input (without organic matter, manure, rice straw, and Gliricidia sepium leaves), with the application dosage 10 t.ha-1 and the second factor comprised of three levels of P fertilizer application (without P addition (control), 50 kg P2O5 ha-1, 100 kg P2O5 ha-1). Results of this study showed that organic matters and P fertilizer application improved soil fertility status, especially pH, soil organic C, cation exchange capacity (CEC), available P which resulted in an increase in P uptake that improve yield of maize. The highest yield of maize (corn cob) was obtained through application Gliricida sepium (8.40 t.ha-1), followed by manure (6.02 t.ha-1) and rice straw (5.87 t.ha-1). Application of 50 kg P2O5 Ha-1 yield was (5.76 t.ha-1) and application of 100 Kg P2O5 Ha-1 yield was (6.12 t.ha-1).
Wu, Junru; Layman, Christopher; Liu, Jun
2004-02-01
A fundamental mathematical framework for applications of Doublet Mechanics to ultrasound propagation in a discrete material is introduced. A multiscale wave equation, dispersion relation for longitudinal waves, and shear waves are derived. The van Hove singularities and corresponding highest frequency limits for the Mth-order wave equations of longitudinal and shear waves are determined for a widely used microbundle structure. Doublet Mechanics is applied to soft tissue and low-density polyethylene. The experimental dispersion data for soft tissue and low-density polyethylene are compared with results predicted by Doublet Mechanics and an attenuation model based on a Kramers-Kronig relation in classical continuum mechanics.
Terahertz Wave Approach and Application on FRP Composites
Kwang-Hee Im
2013-01-01
Full Text Available Terahertz (THz applications have emerged as one of the most new powerful nondestructive evaluation (NDE techniques. A new T-ray time-domain spectroscopy system was utilized for detecting and evaluating orientation influence in carbon fiber-reinforced plastics (CFRPs composite laminates. Investigation of terahertz time-domain spectroscopy (THz-TDS was made, and reflection and transmission configurations were studied as a nondestructive evaluation technique. Here, the CFRP composites derived their excellent mechanical strength, stiffness, and electrical conductivity from carbon fibers. Especially, the electrical conductivity of the CFRP composites depends on the direction of unidirectional fibers since carbon fibers are electrically conducting while the epoxy matrix is not. In order to solve various material properties, the index of refraction (n and the absorption coefficient (α are derived in reflective and transmission configurations using the terahertz time-domain spectroscopy. Also, for a 48-ply thermoplastic polyphenylene-sulfide-(PPS- based CFRP solid laminate and nonconducting materials, the terahertz scanning images were made at the angles ranged from 0° to 180° with respect to the nominal fiber axis. So, the images were mapped out based on the electrical field (E-field direction in the CFRP solid laminates. It is found that the conductivity (σ depends on the angles of the nominal axis in the unidirectional fiber.
Efficient techniques for wave-based sound propagation in interactive applications
Mehra, Ravish
Sound propagation techniques model the effect of the environment on sound waves and predict their behavior from point of emission at the source to the final point of arrival at the listener. Sound is a pressure wave produced by mechanical vibration of a surface that propagates through a medium such as air or water, and the problem of sound propagation can be formulated mathematically as a second-order partial differential equation called the wave equation. Accurate techniques based on solving the wave equation, also called the wave-based techniques, are too expensive computationally and memory-wise. Therefore, these techniques face many challenges in terms of their applicability in interactive applications including sound propagation in large environments, time-varying source and listener directivity, and high simulation cost for mid-frequencies. In this dissertation, we propose a set of efficient wave-based sound propagation techniques that solve these three challenges and enable the use of wave-based sound propagation in interactive applications. Firstly, we propose a novel equivalent source technique for interactive wave-based sound propagation in large scenes spanning hundreds of meters. It is based on the equivalent source theory used for solving radiation and scattering problems in acoustics and electromagnetics. Instead of using a volumetric or surface-based approach, this technique takes an object-centric approach to sound propagation. The proposed equivalent source technique generates realistic acoustic effects and takes orders of magnitude less runtime memory compared to prior wave-based techniques. Secondly, we present an efficient framework for handling time-varying source and listener directivity for interactive wave-based sound propagation. The source directivity is represented as a linear combination of elementary spherical harmonic sources. This spherical harmonic-based representation of source directivity can support analytical, data
Methods and applications of 3-D wave equation common-azimuth prestack migration
CHENG Jiubing; WANG Huazhong; GENG Jianhua; MA Zaitian
2007-01-01
To tackle the difficulties of a 3-D full volum eprestack migration based on the double-square-root (DSR) one-way wave equation in practical applications, the common-azimuth migration approach is first discussed using dual-domain wave propagators under the theoretical frame of crossline common-offset migration. Through coor-dinate transforming, a common-azimuth prestack tau migra-tion technology that recursively continues the source and receiver wavefields and picks up the migrated results in the two-way vertical traveltime (tau) direction is developed.The migrations of synthetic data sets of SEG/EAGE salt model prove that our common-azimuth migration approaches are effective in both depth and tau domains. Two real data examples show the advantages of wave-theory based prestack migration methods in accuracy and imaging resolution over the conventional Kirchhoff integral methods.
A Love Wave Reflective Delay Line with Polymer Guiding Layer for Wireless Sensor Application.
Wang, Wen; He, Shitang
2008-12-05
This paper presents an optimal design for a Love wave reflective delay line on 41(o) YX LiNbO₃ with a polymer guiding layer for wireless sensor applications. A theoretical model was established to describe the Love wave propagation along the larger piezoelectric substrate with polymer waveguide, and the lossy mechanism from the viscoelastic waveguide was discussed, which results in the optimal guiding layer thickness. Coupling of modes (COM) was used to determine the optimal design parameters of the reflective delay line structured by single phase unidirectional transducers (SPUDTs) and shorted grating reflectors. Using the network analyzer, the fabricated Love wave reflective delay line was characterized, high signal noise ratio (S/N), sharp reflection peaks, and few spurious noise between the peaks were found, and the measured result agrees well with the simulated one. Also, the optimal guiding layer thickness of 1.5~1.8μm was extracted experimentally, and it is consistent with the theoretical analysis.
Sussman, Roberto A.
2009-01-01
A numerical approach is considered for spherically symmetric spacetimes that generalize Lemaître Tolman Bondi dust solutions to nonzero pressure (“LTB spacetimes”). We introduce quasilocal (QL) variables that are covariant LTB objects satisfying evolution equations of Friedman Lemaître Robertson Walker (FLRW) cosmologies. We prove rigorously that relative deviations of the local covariant scalars from the QL scalars are nonlinear, gauge invariant and covariant perturbations on a FLRW formal background given by the QL scalars. The dynamics of LTB spacetimes is completely determined by the QL scalars and these exact perturbations. Since LTB spacetimes are compatible with a wide variety of “equations of state,” either single fluids or mixtures, a large number of known solutions with dark matter and dark energy sources in a FLRW framework (or with linear perturbations) can be readily examined under idealized but nontrivial inhomogeneous conditions. Coordinate choices and initial conditions are derived for a numerical treatment of the perturbation equations, allowing us to study nonlinear effects in a variety of phenomena, such as gravitational collapse, nonlocal effects, void formation, dark matter and dark energy couplings, and particle creation. In particular, the embedding of inhomogeneous regions can be performed by a smooth matching with a suitable FLRW solution, thus generalizing the Newtonian “top hat” models that are widely used in astrophysical literature. As examples of the application of the formalism, we examine numerically the formation of a black hole in an expanding Chaplygin gas FLRW universe, as well as the evolution of density clumps and voids in an interactive mixture of cold dark matter and dark energy.
Advances in condensed matter optics
Chen, Liangyao; Jiang, Xunya; Jin, Kuijuan; Liu, Hui; Zhao, Haibin
2015-01-01
This book describes some of the more recent progresses and developmentsin the study of condensed matter optics in both theoretic and experimental fields.It will help readers, especially graduate students and scientists who are studying and working in the nano-photonic field, to understand more deeply the characteristics of light waves propagated in nano-structure-based materials with potential applications in the future.
Application of CHAD hydrodynamics to shock-wave problems
Trease, H.E.; O`Rourke, P.J.; Sahota, M.S. [Los Alamos National Lab., NM (United States)
1997-12-31
CHAD is the latest in a sequence of continually evolving computer codes written to effectively utilize massively parallel computer architectures and the latest grid generators for unstructured meshes. Its applications range from automotive design issues such as in-cylinder and manifold flows of internal combustion engines, vehicle aerodynamics, underhood cooling and passenger compartment heating, ventilation, and air conditioning to shock hydrodynamics and materials modeling. CHAD solves the full unsteady Navier-Stoke equations with the k-epsilon turbulence model in three space dimensions. The code has four major features that distinguish it from the earlier KIVA code, also developed at Los Alamos. First, it is based on a node-centered, finite-volume method in which, like finite element methods, all fluid variables are located at computational nodes. The computational mesh efficiently and accurately handles all element shapes ranging from tetrahedra to hexahedra. Second, it is written in standard Fortran 90 and relies on automatic domain decomposition and a universal communication library written in standard C and MPI for unstructured grids to effectively exploit distributed-memory parallel architectures. Thus the code is fully portable to a variety of computing platforms such as uniprocessor workstations, symmetric multiprocessors, clusters of workstations, and massively parallel platforms. Third, CHAD utilizes a variable explicit/implicit upwind method for convection that improves computational efficiency in flows that have large velocity Courant number variations due to velocity of mesh size variations. Fourth, CHAD is designed to also simulate shock hydrodynamics involving multimaterial anisotropic behavior under high shear. The authors will discuss CHAD capabilities and show several sample calculations showing the strengths and weaknesses of CHAD.
Broyd, Christopher J; Nijjer, Sukhjinder; Sen, Sayan; Petraco, Ricardo; Jones, Siana; Al-Lamee, Rasha; Foin, Nicolas; Al-Bustami, Mahmud; Sethi, Amarjit; Kaprielian, Raffi; Ramrakha, Punit; Khan, Masood; Malik, Iqbal S; Francis, Darrel P; Parker, Kim; Hughes, Alun D; Mikhail, Ghada W; Mayet, Jamil; Davies, Justin E
2016-03-01
Wave intensity analysis (WIA) has found particular applicability in the coronary circulation where it can quantify traveling waves that accelerate and decelerate blood flow. The most important wave for the regulation of flow is the backward-traveling decompression wave (BDW). Coronary WIA has hitherto always been calculated from invasive measures of pressure and flow. However, recently it has become feasible to obtain estimates of these waveforms noninvasively. In this study we set out to assess the agreement between invasive and noninvasive coronary WIA at rest and measure the effect of exercise. Twenty-two patients (mean age 60) with unobstructed coronaries underwent invasive WIA in the left anterior descending artery (LAD). Immediately afterwards, noninvasive LAD flow and pressure were recorded and WIA calculated from pulsed-wave Doppler coronary flow velocity and central blood pressure waveforms measured using a cuff-based technique. Nine of these patients underwent noninvasive coronary WIA assessment during exercise. A pattern of six waves were observed in both modalities. The BDW was similar between invasive and noninvasive measures [peak: 14.9 ± 7.8 vs. -13.8 ± 7.1 × 10(4) W·m(-2)·s(-2), concordance correlation coefficient (CCC): 0.73, P Exercise increased the BDW: at maximum exercise peak BDW was -47.0 ± 29.5 × 10(4) W·m(-2)·s(-2) (P < 0.01 vs. rest) and cumulative BDW -19.2 ± 12.6 × 10(3) W·m(-2)·s(-1) (P < 0.01 vs. rest). The BDW can be measured noninvasively with acceptable reliably potentially simplifying assessments and increasing the applicability of coronary WIA.
Li, Bohua; Rindler-Daller, Tanja
2016-01-01
We consider an alternative dark matter candidate, ultralight bosonic dark matter ($m>10^{-22}$eV) described by a complex scalar field (SFDM) with a global U(1) symmetry, for which the associated charge density is conserved after particle production during standard reheating (w=0). We allow for a repulsive self-interaction. In a Lambda-SFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiationlike (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the radiation-dominated era, there is an earlier era of stiff-SFDM-domination. Transitions between these eras, determined by SFDM particle mass $m$ and the quartic self-interaction coupling strength $\\lambda$, are thus constrained by cosmological observables, particularly N_{eff}, the effective number of neutrino species during BBN, and z_{eq}, the redshift of matter-radiation equality. Furthermore, since the stochastic gravitational wave background (SGWB) from inflation is amplified during the stiff era, it can contribute...
On the application of Particle Swarm Optimization strategies on Scholte-wave inversion
Wilken, D.; Rabbel, W.
2012-07-01
We investigate different aspects concerning the application of swarm intelligence optimization to the inversion of Scholte-wave phase-slowness frequency (p-f) spectra with respect to shear wave velocity structure. Besides human influence due to the dependence on a priori information for starting models and interpretation of p-f spectra as well as noise, the model resolution of the inversion problem is strongly influenced by the multimodality of the misfit function. We thus tested the efficiency of global, stochastic optimization approaches with focus on swarm intelligence methods that can explore the multiple minima of the misfit function. A comparison among different PSO schemes by applying them to synthetic Scholte-wave spectra led to a hybrid of Particle Swarm Optimization and Downhill Simplex providing the best resolution of inverted shear wave velocity depth models. The results showed a very low spread of best fitting solutions of 7 per cent in shear wave velocity and an average of 9 per cent for noisy synthetic data and a very good fit to the true synthetic model used for computation of the input data. To classify this method we also compared the probability of finding a good fit in synthetic spectra inversion with that of Evolutionary Algorithm, Simulated Annealing, Neighbourhood Algorithm and Artificial Bee Colony algorithm. Again the hybrid optimization scheme showed its predominance. The usage of stochastic algorithms furthermore allowed a new way of misfit definition in terms of dispersion curve slowness residuals making the inversion scheme independent on Scholte-wave mode identification and allowing joint inversion of fundamental mode and higher mode information. Finally we used the hybrid optimization scheme and the misfit calculation for the inversion of 2-D shear wave velocity profiles from two locations in the North- and Baltic Sea. The models show acceptable resolution and a very good structural correlation to high resolution reflection seismic
Application of particle swarm optimization to interpret Rayleigh wave dispersion curves
Song, Xianhai; Tang, Li; Lv, Xiaochun; Fang, Hongping; Gu, Hanming
2012-09-01
Rayleigh waves have been used increasingly as an appealing tool to obtain near-surface shear (S)-wave velocity profiles. However, inversion of Rayleigh wave dispersion curves is challenging for most local-search methods due to its high nonlinearity and to its multimodality. In this study, we proposed and tested a new Rayleigh wave dispersion curve inversion scheme based on particle swarm optimization (PSO). PSO is a global optimization strategy that simulates the social behavior observed in a flock (swarm) of birds searching for food. A simple search strategy in PSO guides the algorithm toward the best solution through constant updating of the cognitive knowledge and social behavior of the particles in the swarm. To evaluate calculation efficiency and stability of PSO to inversion of surface wave data, we first inverted three noise-free and three noise-corrupted synthetic data sets. Then, we made a comparative analysis with genetic algorithms (GA) and a Monte Carlo (MC) sampler and reconstructed a histogram of model parameters sampled on a low-misfit region less than 15% relative error to further investigate the performance of the proposed inverse procedure. Finally, we inverted a real-world example from a waste disposal site in NE Italy to examine the applicability of PSO on Rayleigh wave dispersion curves. Results from both synthetic and field data demonstrate that particle swarm optimization can be used for quantitative interpretation of Rayleigh wave dispersion curves. PSO seems superior to GA and MC in terms of both reliability and computational efforts. The great advantages of PSO are fast in locating the low misfit region and easy to implement. Also there are only three parameters to tune (inertia weight or constriction factor, local and global acceleration constants). Theoretical results exist to explain how to tune these parameters.
Farman Ali Mangi
2016-01-01
Full Text Available A multiband circular polarizer based on fission transmission of linearly polarized wave for x-band application is proposed, which is constructed of 2 × 2 metallic strips array. The linear-to-circular polarization conversion is obtained by decomposing the linearly incident x-polarized wave into two orthogonal vector components of equal amplitude and 90° phase difference between them. The innovative approach of “fission transmission of linear-to-circular polarized wave” is firstly introduced to obtain giant circular dichroism based on decomposition of orthogonal vector components through the structure. It means that the incident linearly polarized wave is converted into two orthogonal components through lower printed metallic strips layer and two transmitted waves impinge on the upper printed strips layer to convert into four orthogonal vector components at the end of structure. This projection and transmission sequence of orthogonal components sustain the chain transmission of electromagnetic wave and can achieve giant circular dichroism. Theoretical analysis and microwave experiments are presented to validate the performance of the structure. The measured results are in good agreement with simulation results. In addition, the proposed circular polarizer exhibits the optimal performance with respect to the normal incidence. The right handed circularly polarized wave is emitted ranging from 10.08 GHz to 10.53 GHz and 10.78 GHz to 11.12 GHz, while the left handed circular polarized wave is excited at 10.54 GHz–10.70 GHz and 11.13 GHz–11.14 GHz, respectively.
Li Xiao-Ming; Chen Shuang-Quan; Li Xiang-Yang
2013-01-01
Several parameters are needed to describe the converted-wave (C-wave) moveout in processing multi-component seismic data, because of asymmetric raypaths and anisotropy. As the number of parameters increases, the converted wave data processing and analysis becomes more complex. This paper develops a new moveout equation with two parameters for C-waves in vertical transverse isotropy (VTI) media. The two parameters are the C-wave stacking velocity (VC2) and the squared velocity ratio (γvti) between the horizontal P-wave velocity and C-wave stacking velocity. The new equation has fewer parameters, but retains the same applicability as previous ones. The applicability of the new equation and the accuracy of the parameter estimation are checked using model and real data. The form of the new equation is the same as that for layered isotropic media. The new equation can simplify the procedure for C-wave processing and parameter estimation in VTI media, and can be applied to real C-wave processing and interpretation. Accurate VC2 andγvti can be deduced from C-wave data alone using the double-scanning method, and the velocity ratio model is suitable for event matching between P-and C-wave data.
Particulate matter emissions from combustion of wood in district heating applications
Ghafghazi, S. [University of British Columbia, Vancouver; Sowlati, T. [University of British Columbia, Vancouver; Sokhansanj, Shahabaddine [ORNL; Bi, X.T. [University of British Columbia, Vancouver; Melin, Staffan [Delta Research Corporation
2011-01-01
The utilization of wood biomass to generate district heat and power in communities that have access to this energy source is increasing. In this paper the effect of wood fuel properties, combustion condition, and flue gas cleaning system on variation in the amount and formation of particles in the flue gas of typical district heating wood boilers are discussed based on the literature survey. Direct measurements of particulate matter (PM) emissions from wood boilers with district heating applications are reviewed and presented. Finally, recommendations are given regarding the selection of wood fuel, combustion system condition, and flue gas cleaning system in district heating systems in order to meet stringent air quality standards. It is concluded that utilization of high quality wood fuel, such as wood pellets produced from natural, uncontaminated stem wood, would generate the least PM emissions compared to other wood fuel types. Particulate matter emissions from grate burners equipped with electrostatic precipitators when using wood pellets can be well below stringent regulatory emission limit such as particulate emission limit of Metro Vancouver, Canada.
CLINICAL APPLICATION OF SHOCK WAVE THERAPY IN MUSCULOSKELETAL DISORDERS: PART I.
Saggini, R; Di Stefano, A; Saggini, A; Bellomo, R G
2015-01-01
The shock wave has been widely recognized in literature as a biological regulator; therefore we carried out a review on the activity performed by shock waves on the bone-myofascial tissue system. To date, the application of Shock Wave Therapy (SWT) in musculoskeletal disorders has been primarily used in the treatment of tendinopathies (proximal plantar fasciopathy, lateral elbow tendinopathy, calcific tendinopathy of the shoulder, and patellar tendinopathy, etc.) and bone defects (delayed- and non-union of bone fractures, avascular necrosis of femoral head, etc.). Although the mechanism of their therapeutic effects is still unknown, the majority of published papers have shown positive and beneficial effects of using SWT as a treatment for musculoskeletal disorders, with a success rate ranging from 65 to 91%, while the complications are low or negligible. The purpose of this paper is to inform the reader about the published data on the clinical application of SWT in the treatment of musculoskeletal disorders. In this paper, with the help of a literature review, indications and success rates for SWT in the treatment of musculoskeletal disorders are outlined, while adequate SWT parameters (e.g., rate of impulses, energy flux density, etc.) are defined according to the present state of knowledge. Given the abundance of the argument, it seems appropriate to subdivide the review into two parts, the first concerning the evidence of Extracorporeal Shock Wave Therapy (ESWT) on bone disorders, the second concerning findings on tendon and muscle treatment.
Stratakis, Diktys; Rogers, Chris T; Alekou, Androula; Pasternak, Jaroslaw
2014-01-01
An ionization cooling channel is a tightly spaced lattice containing absorbers for reducing the momentum of the muon beam, rf cavities for restoring the longitudinal momentum, and strong solenoids for focusing. Such a lattice can be an essential feature for fundamental high-energy physics applications. In this paper we design, simulate, and compare four individual cooling schemes that rely on ionization cooling. We establish a scaling characterizing the impact of rf gradient limitations on the overall performance and systematically compare important lattice parameters such as the required magnetic fields and the number of cavities and absorber lengths for each cooling scenario. We discuss approaches for reducing the peak magnetic field inside the rf cavities by either increasing the lattice cell length or adopting a novel bucked-coil configuration. We numerically examine the performance of our proposed channels with two independent codes that fully incorporate all basic particle-matter-interaction physical pr...
Diktys Stratakis
2014-07-01
Full Text Available An ionization cooling channel is a tightly spaced lattice containing absorbers for reducing the momentum of the muon beam, rf cavities for restoring the longitudinal momentum, and strong solenoids for focusing. Such a lattice can be an essential feature for fundamental high-energy physics applications. In this paper we design, simulate, and compare four individual cooling schemes that rely on ionization cooling. We establish a scaling characterizing the impact of rf gradient limitations on the overall performance and systematically compare important lattice parameters such as the required magnetic fields and the number of cavities and absorber lengths for each cooling scenario. We discuss approaches for reducing the peak magnetic field inside the rf cavities by either increasing the lattice cell length or adopting a novel bucked-coil configuration. We numerically examine the performance of our proposed channels with two independent codes that fully incorporate all basic particle-matter-interaction physical processes.
Secondary Ion Mass Spectrometry: The Application in the Analysis of Atmospheric Particulate Matter
Huang, Di; Hua, Xin; Xiu, Guangli; Zheng, Yongjie; Yu, Xiao-Ying; Long, Yi-Tao
2017-07-24
Currently, considerable attention has been paid to atmospheric particulate matter (PM) investigation due to its importance in human health and global climate change. Surface characterization of PM is important since the chemical heterogeneity between the surface and bulk may vary its impact on the environment and human being. Secondary ion mass spectrometry (SIMS) is a surface technique with high surface sensitivity, capable of high spatial chemical imaging and depth profiling. Recent research shows that SIMS holds great potential in analyzing both surface and bulk chemical information of PM. In this review, we presented the working principal of SIMS in PM characterization, summarized recent applications in PM analysis from different sources, discussed its advantages and limitations, and proposed the future development of this technique with a perspective in environmental sciences.
This book is dedicated to various aspects of electromagnetic wave theory and its applications in science and technology. The covered topics include the fundamental physics of electromagnetic waves, theory of electromagnetic wave propagation and scattering, methods of computational analysis......, material characterization, electromagnetic properties of plasma, analysis and applications of periodic structures and waveguide components, etc....
A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber
Chiang, W. Y.; Wu, M. H.; Wu, K. L.; Lin, M. H.; Teng, H. H.; Barnett, L. R.; Chu, K. R., E-mail: krchu@yahoo.com.tw [Department of Physics, National Taiwan University, Taipei, Taiwan (China); Tsai, Y. F.; Ko, C. C.; Yang, E. C. [Department of Entomology, National Taiwan University, Taipei, Taiwan (China); Jiang, J. A. [Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taipei, Taiwan (China)
2014-08-15
Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.
A microwave applicator for uniform irradiation by circularly polarized waves in an anechoic chamber
Chiang, W. Y.; Wu, M. H.; Wu, K. L.; Lin, M. H.; Teng, H. H.; Tsai, Y. F.; Ko, C. C.; Yang, E. C.; Jiang, J. A.; Barnett, L. R.; Chu, K. R.
2014-08-01
Microwave applicators are widely employed for materials heating in scientific research and industrial applications, such as food processing, wood drying, ceramic sintering, chemical synthesis, waste treatment, and insect control. For the majority of microwave applicators, materials are heated in the standing waves of a resonant cavity, which can be highly efficient in energy consumption, but often lacks the field uniformity and controllability required for a scientific study. Here, we report a microwave applicator for rapid heating of small samples by highly uniform irradiation. It features an anechoic chamber, a 24-GHz microwave source, and a linear-to-circular polarization converter. With a rather low energy efficiency, such an applicator functions mainly as a research tool. This paper discusses the significance of its special features and describes the structure, in situ diagnostic tools, calculated and measured field patterns, and a preliminary heating test of the overall system.
Djenaine de Souza
2004-10-01
Full Text Available The aim of this work is to discuss some selected applications of square wave voltammetry published in the last five years. The applications focused here cover several electroanalytical fields such as: determination of pesticides; molecules with biological activity; metals and other environmental pollutants. Special attention is given to the work developed in the Grupo de Materiais Eletroquímicos e Métodos Eletroanalíticos - IQSC - USP concerning the utilization of square wave voltammetry, with different kinds of electrodes, for the determination of pesticides in natural waters and active principles in pharmaceutical formulations. The new methodology is simple, fast and sensitive when compared with the traditional ones such as chromatography and spectrophotometry. The satisfactory results obtained provide alternative procedures for the quality control of drugs and the monitoring of pesticides in natural environments.
First long-term application of squeezed states of light in a gravitational-wave observatory.
Grote, H; Danzmann, K; Dooley, K L; Schnabel, R; Slutsky, J; Vahlbruch, H
2013-05-03
We report on the first long-term application of squeezed vacuum states of light to improve the shot-noise-limited sensitivity of a gravitational-wave observatory. In particular, squeezed vacuum was applied to the German-British detector GEO 600 during a period of three months from June to August 2011, when GEO 600 was performing an observational run together with the French-Italian Virgo detector. In a second period, the squeezing application continued for about 11 months from November 2011 to October 2012. During this time, squeezed vacuum was applied for 90.2% (205.2 days total) of the time that science-quality data were acquired with GEO 600. A sensitivity increase from squeezed vacuum application was observed broadband above 400 Hz. The time average of gain in sensitivity was 26% (2.0 dB), determined in the frequency band from 3.7 to 4.0 kHz. This corresponds to a factor of 2 increase in the observed volume of the Universe for sources in the kHz region (e.g., supernovae, magnetars). We introduce three new techniques to enable the long-term application of squeezed light, and show that the glitch rate of the detector did not increase from squeezing application. Squeezed vacuum states of light have arrived as a permanent application, capable of increasing the astrophysical reach of gravitational-wave detectors.
Introduction and Application of Kinematic Wave Routing Techniques Using HEC-1.
1979-05-01
WAVE ROUTING TECHNIQUES USING HEC-1 47 - 80 Johannes J. DeVries Chapter 2 provides a discussion of the necessary information required to apply kinematic...solution techniques. The following chapter will present additional background information and the details necessary for the effective application of...procedure for verifying its ability to correctly simulate the behavoir of a given basin is strongly discouraged. 1Hydraulic Engineer, Training & Methods
On-Wafer Characterization of Millimeter-Wave Antennas for Wireless Applications
Simons, Rainee N.; Lee, Richard Q.
1998-01-01
The paper demonstrates a de-embedding technique and a direct on-substrate measurement technique for fast and inexpensive characterization of miniature antennas for wireless applications at millimeter-wave frequencies. The technique is demonstrated by measurements on a tapered slot antenna (TSA). The measured results at Ka-Band frequencies include input impedance, mutual coupling between two TSAs and absolute gain of TSA.
Dhakal, Pashupati, E-mail: dhakal@jlab.org; Ciovati, Gianluigi, E-mail: gciovati@jlab.org; Myneni, Ganapati R., E-mail: rao@jlab.org [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606 (United States)
2015-12-04
Future continuous wave (CW) accelerators require the superconducting radio frequency cavities with high quality factor and medium accelerating gradients (≤20 MV/m). Ingot niobium cavities with medium purity fulfill the specifications of both accelerating gradient and high quality factor with simple processing techniques and potential reduction in cost. This contribution reviews the current superconducting radiofrequency research and development and outlines the potential benefits of using ingot niobium technology for CW applications.
The Bloch wave operator: generalizations and applications: Part I. The time-independent case
Killingbeck, John P [Mathematics Department, University of Hull, Hull HU6 7RX (United Kingdom); Jolicard, Georges [Observatoire de Besancon (UMR-CNRS 6091), Universite de Franche-Comte, 41 bis, Avenue de l' Observatoire, 25000 Besancon (France)
2003-05-23
This is part 1 of a two-part review on wave operator theory and methods. The basic theory of the time-independent wave operator is presented in terms of partitioned matrix theory for the benefit of general readers, with a discussion of the links between the matrix and projection operator approaches. The matrix approach is shown to lead to simple derivations of the wave operators and effective Hamiltonians of Loewdin, Bloch, Des Cloizeaux and Kato as well as to some associated variational forms. The principal approach used throughout stresses the solution of the nonlinear equation for the reduced wave operator, leading to the construction of the effective Hamiltonians of Bloch and of Des Cloizeaux. Several mathematical techniques which are useful in implementing this approach are explained, some of them being relatively little known in the area of wave operator calculations. The theoretical discussion is accompanied by several specimen numerical calculations which apply the described techniques to a selection of test matrices taken from the previous literature on wave operator methods. The main emphasis throughout is on the use of numerical methods which use iterative or perturbation algorithms, with simple Pade approximant methods being found sufficient to deal with most of the cases of divergence which are encountered. The use of damping factors and relaxation parameters is found to be effective in stabilizing calculations which use the energy-dependent effective Hamiltonian of Loewdin. In general the computations suggest that the numerical applications of the nonlinear equation for the reduced wave operator are best carried out with the equation split into a pair of equations in which the Bloch effective Hamiltonian appears as a separate entity. The presentation of the theoretical and computational details throughout is accompanied by references to and discussion of many works which have used wave operator methods in physics, chemistry and engineering. Some of
Designing slow-light photonic crystal waveguides for four-wave mixing applications.
Kanakis, Panagiotis; Kamalakis, Thomas; Sphicopoulos, Thomas
2014-02-15
We discuss the optimization of photonic crystal waveguides for four-wave mixing (FWM) applications, taking into account linear loss and free-carrier effects. Suitable figures of merit are introduced in order to guide us through the choice of practical, high-efficiency designs requiring relatively low pump power and small waveguide length. In order to realistically perform the waveguide optimization process, we propose and validate an approximate expression for the FWM efficiency, which significantly alleviates our numerical calculations. Promising waveguide designs are identified by means of an exhaustive search, altering some structural parameters. Our approach aims to optimize the waveguides for nonlinear signal-processing applications based on the FWM.
A. Gaebler
2009-01-01
Full Text Available Novel approaches of tunable devices for millimeter wave applications based on liquid crystal (LC are presented. In the first part of the paper, a novel concept of a tunable LC phase shifter realized in Low Temperature Cofired Ceramics technology is shown while the second part of the paper deals with a tunable high-gain antenna based on an LC tunable reflectarray. The reflectarray features continuously beam scanning in between ±25∘. Also first investigations on radiation hardness of LCs are carried out, indicating that LCs might be suitable for space applications.
Wave-based liquid-interface metamaterials
Francois, N; Xia, H; Punzmann, H; Fontana, P W; Shats, M
2017-01-01
The control of matter motion at liquid–gas interfaces opens an opportunity to create two-dimensional materials with remotely tunable properties. In analogy with optical lattices used in ultra-cold atom physics, such materials can be created by a wave field capable of dynamically guiding matter into periodic spatial structures. Here we show experimentally that such structures can be realized at the macroscopic scale on a liquid surface by using rotating waves. The wave angular momentum is transferred to floating micro-particles, guiding them along closed trajectories. These orbits form stable spatially periodic patterns, the unit cells of a two-dimensional wave-based material. Such dynamic patterns, a mirror image of the concept of metamaterials, are scalable and biocompatible. They can be used in assembly applications, conversion of wave energy into mean two-dimensional flows and for organising motion of active swimmers. PMID:28181490
CMS-Wave Model: Part 4. An Automated Procedure for CMS-Wave in Resource-Demanding Applications
2011-04-01
user’s manual for CMS -Wave are available (Lin et al. 2008, 2006; Demirbilek et al. 2007). CMS -Wave is part of the Coastal Modeling System developed...at the same level as the subfolders. Figure 2 shows the contents of the Visser_1991 example subfolder, including two CMS -Wave simulations, named as...and the surrounding area (red line denotes the CMS domain). The Coastal Modeling System ( CMS ) was applied to evaluate current and sedimentation
Understanding the Core-Halo Relation of Quantum Wave Dark Matter, $\\psi$DM, from 3D Simulations
Schive, Hsi-Yu; Woo, Tak-Pong; Wong, Shing-Kwong; Chiueh, Tzihong; Broadhurst, Tom; Hwang, W-Y Pauchy
2014-01-01
We examine the nonlinear structure of gravitationally collapsed objects that form in our simulations of wavelike cold dark matter ($\\psi$DM), described by the Schr\\"odinger-Poisson (SP) equation. A distinct gravitationally self-bound solitonic core is found at the center of every halo, with a profile quite different from cores modeled in the warm or self-interacting dark matter scenarios. Furthermore, we show that each solitonic core is surrounded by an extended halo composed of large fluctuating dark matter granules which modulate the halo density on a scale comparable to the diameter of the solitonic core. The scaling symmetry of the SP equation and the uncertainty principle tightly relate the core mass to the halo specific energy, which, in the context of cosmological structure formation, leads to a simple scaling between core mass ($M_c$) and halo mass ($M_h$), $M_c \\propto a^{-1/2} M_h^{1/3}$, where $a$ is the cosmic scale factor. We verify this scaling relation by (i) examining the internal structure of...
2011-03-02
... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION In the Matter of Progress Energy Florida, Inc. (Combined License Application, Levy County Nuclear... relating to pending appeal filed by the Nuclear Regulatory Commission staff in this case. Mr. Dehmel has...
Slow waves in microchannel metal waveguides and application to particle acceleration
L. C. Steinhauer
2003-06-01
Full Text Available Conventional metal-wall waveguides support waveguide modes with phase velocities exceeding the speed of light. However, for infrared frequencies and guide dimensions of a fraction of a millimeter, one of the waveguide modes can have a phase velocity equal to or less than the speed of light. Such a metal microchannel then acts as a slow-wave structure. Furthermore, if it is a transverse magnetic mode, the electric field has a component along the direction of propagation. Therefore, a strong exchange of energy can occur between a beam of charged particles and this slow-waveguide mode. Moreover, the energy exchange can be sustained over a distance limited only by the natural damping of the wave. This makes the microchannel metal waveguide an attractive possibility for high-gradient electron laser acceleration because the wave can be directly energized by a long-wavelength laser. Indeed the frequency of CO_{2} lasers lies at a fortuitous wavelength that produces a strong laser-particle interaction in a channel of reasonable macroscopic size (e.g., ∼0.6 mm. The dispersion properties including phase velocity and damping for the slow wave are developed. The performance and other issues related to laser accelerator applications are discussed.
Mara Lucia Jacinto Oliveira
2015-02-01
Full Text Available Tannery sludge contains high concentrations of inorganic elements, such as chromium (Cr, which may lead to environmental pollution and affect human health The behavior of Cr in organic matter fractions and in the growth of cowpea (Vigna unguiculata L. was studied in a sandy soil after four consecutive annual applications of composted tannery sludge (CTS. Over a four-year period, CTS was applied on permanent plots (2 × 5 m and incorporated in the soil (0-20 cm at the rates of 0, 2.5, 5.0, 10.0, and 20.0 Mg ha-1 (dry weight basis. These treatments were replicated four times in a randomized block design. In the fourth year, cowpea was planted and grown for 50 days, at which time we analyzed the Cr concentrations in the soil, in the fulvic acid, humic acid, and humin fractions, and in the leaves, pods, and grains of cowpea. Composted tannery sludge led to an increase in Cr concentration in the soil. Among the humic substances, the highest Cr concentration was found in humin. The application rates of CTS significantly increased Cr concentration in leaves and grains.
Vera M. Kolb
2010-06-01
Full Text Available The connection between astrobiology and green chemistry represents a new approach to sustainability of organic matter on asteroids or similar bodies. Green chemistry is chemistry which is environmentally friendly. One obvious way for chemistry to be green is to use water as a solvent, instead of more toxic organic solvents. Many astrobiological reactions occur in the aqueous medium, for example in the prebiotic soup or during the aqueous alteration period on asteroids. Thus any advances in the green organic reactions in water are directly applicable to astrobiology. Another green chemistry approach is to abolish use of toxic solvents. This can be accomplished by carrying out the reactions without a solvent in the solventless or solid-state reactions. The advances in these green reactions are directly applicable to the chemistry on asteroids during the periods when water was not available. Many reactions on asteroids may have been done in the solid mixtures. These reactions may be responsible for a myriad of organic compounds that have been isolated from the meteorites.
Li Biao; Li Yuqi [Nonlinear Science Center, Ningbo University, Ningbo 315211 (China); Zhang Xiaofei; Liu, W M, E-mail: biaolee2000@yahoo.com.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2011-09-14
We present two families of one-soliton solutions and three families of two-soliton solutions for a generalized nonlinear Schroedinger equation, which is characterized by the time-dependent scattering length and varying potentials. Then, we investigate the propagation of one-soliton and interactions of two-soliton by some selected control functions. The results show that the intensities of one- and two-soliton first increase rapidly to a peak value, and then decay very slowly to the background value; thus, the lifetimes of both one-soliton and two-soliton in Bose-Einstein condensates can be extended largely at least to the order of the lifetime of a Bose-Einstein condensate in real experiments. Our results open up new ways of considerable experimental interest for the management of matter-wave solitons in Bose-Einstein condensates.
Belobo Belobo, D; Ben-Bolie, G H; Kofane, T C
2015-04-01
By using the F-expansion method associated with four auxiliary equations, i.e., the Bernoulli equation, the Riccati equation, the Lenard equation, and the hyperbolic equation, we present exact explicit solutions describing the dynamics of matter-wave condensates with time-varying two- and three-body nonlinearities. Condensates are trapped in a harmonic potential and they exchange atoms with the thermal cloud. These solutions include the generalized Jacobi elliptic function solutions, hyperbolic function solutions, and trigonometric function solutions. In addition, we have also found rational function solutions. Solutions constructed here have many free parameters that can be used to manipulate and control some important features of the condensate, such as the position, width, velocity, acceleration, and homogeneous phase. The stability of the solutions is confirmed by their long-time numerical behavior.
Impedance Matching for Discrete, Periodic Media and Application to Two-Scale Wave Propagation Models
Thirunavukkarasu, Senganal
This dissertation introduces the idea of an equivalent continuous medium (ECM) that has the same impedance as that of an unbounded discrete periodic medium. Contrary to existing knowledge, we constructively show that it is indeed possible to achieve perfect matching for periodic and discrete media. We present analytical results relating the propagation characteristics of periodic media and the corresponding ECM, leading to the development of numerical methods for wave propagation in these media. In this dissertation, we present the main idea of ECM and apply it, with mixed results, to seemingly different problems requiring effective numerical methods for modeling wave propagation in unbounded media. An immediate application of ECM is in developing absorbing boundary conditions (ABCs) for wave propagation in unbounded discrete media. Using the idea of ECM, and building on class of continuous ABCs called perfectly matched discrete layers (PMDL), we propose a new class of discrete ABCs called discrete PMDL and develop frequency domain formulations that are shown to be superior to continuous ABCs. Another application that is explored in this dissertation is the design of interface conditions for concurrent coupling of two-scale wave propagation models, e.g. Atomistic-to-Continuum (AtC) coupling. We propose a domain-decomposition (DD) approach and develop accurate interface conditions that are critical for the concurrent coupling of the two-scale models. It turns out that time-domain discrete ABCs are key to the the accuracy of these interface conditions. Since discrete PMDL is well-posed and accurate for the model problem, we build on it to propose an efficient and accurate interface condition for two-scale wave propagation models. Although many open problems remain with respect to implementation, we believe that the proposed DD based approach is a good first step towards achieving efficient coupling of two-scale wave propagation models. Time-domain discrete PMDL can
2006-01-01
This paper presents the methodology for the energy flow analysis of coupled Timoshenko beam structures and various numerical applications to verify the developed methodology. To extend the application of the energy flow model for corrected flexural waves in the Timoshenko beam, which is developed in the other companion paper, to coupled structures, the wave transmission analyses of general coupled Timoshenko beam systems are performed. First, power transmission and reflection coefficients for...
Stadnik, Y. V.; Flambaum, V. V.
2016-06-01
We outline laser interferometer measurements to search for variation of the electromagnetic fine-structure constant α and particle masses (including a nonzero photon mass). We propose a strontium optical lattice clock—silicon single-crystal cavity interferometer as a small-scale platform for these measurements. Our proposed laser interferometer measurements, which may also be performed with large-scale gravitational-wave detectors, such as LIGO, Virgo, GEO600, or TAMA300, may be implemented as an extremely precise tool in the direct detection of scalar dark matter that forms an oscillating classical field or topological defects.
A method for separating O-wave and X-wave and its application in digital ionosonde
Wang Shun
2014-01-01
Full Text Available Separation for O wave and X wave is a very important job in interpretation of ionograms, which is premise for automatic scaling. In this paper, a new digital method for separating O wave and X wave is presented, based on a numerical synthesizing technique, which is different from using image recognition to separate trace O and trace X in the ionograms, and from using the electrical method to synthesize and detect circularly polarized waves. By replacing analog phase shifters and switches in existing ionosonde with digital phase shifters with different initial phase, 0°, +90°, −90°, circularly polarized waves are synthesized digitally within the range of 1-30 MHz, which eliminates the nonlinearity and expands the bandwidth of the ionosonde, and there is no need to switch the analog switches continuously. The new method has been successfully applied to CAS-DIS ionosonde and testing results show that the new digital method is capable of separating O wave and X wave well.
1988-10-18
Mantle Boundary Inferred from Short-Period Scattered PKP Waves Recorded at the Global Digital Seismograph Network KLAUS BATAILLE AND STANILY M. F...Geophys. Res., 78, Osemov, L A., Wave Propagation in a Random Medium, Mc Graw - 6009--6020, 1973. Hill, New York, 1960. Morelli, A., and A. M
Elastic wavelets and their application to problems of solitary wave propagation
Cattani, Carlo
2008-03-01
Full Text Available The paper can be referred to that direction in the wavelet theory, which was called by Kaiser "the physical wavelets". He developed the analysis of first two kinds of physical wavelets - electromagnetic (optic and acoustic wavelets. Newland developed the technique of application of harmonic wavelets especially for studying the harmonic vibrations. Recently Cattani and Rushchitsky proposed the 4th kind of physical wavelets - elastic wavelets. This proposal was based on three main elements: 1. Kaiser's idea of constructing the physical wavelets on the base of specially chosen (admissible solutions of wave equations. 2. Developed by one of authors theory of solitary waves (with profiles in the form of Chebyshov-Hermite functions propagated in elastic dispersive media. 3. The theory and practice of using the wavelet "Mexican Hat" system, the mother and farther wavelets (and their Fourier transforms of which are analytically represented as the Chebyshov-Hermite functions of different indexes. An application of elastic wavelets to studying the evolution of solitary waves of different shape during their propagation through composite materials is shown on many examples.
Inertial quantum sensors using light and matter
Barrett, B.; Bertoldi, A.; Bouyer, P.
2016-05-01
The past few decades have seen dramatic progress in our ability to manipulate and coherently control matter-waves. Although the duality between particles and waves has been well tested since de Broglie introduced the matter-wave analog of the optical wavelength in 1924, manipulating atoms with a level of coherence that enables one to use these properties for precision measurements has only become possible with our ability to produce atomic samples exhibiting temperatures of only a few millionths of a degree above absolute zero. Since the initial experiments a few decades ago, the field of atom optics has developed in many ways, with both fundamental and applied significance. The exquisite control of matter waves offers the prospect of a new generation of force sensors exhibiting unprecedented sensitivity and accuracy, for applications from navigation and geophysics to tests of general relativity. Thanks to the latest developments in this field, the first commercial products using this quantum technology are now available. In the future, our ability to create large coherent ensembles of atoms will allow us an even more precise control of the matter-wave and the ability to create highly entangled states for non-classical atom interferometry.
Campbell, Eleanor E.; Paustian, Keith
2015-12-01
Soil organic matter (SOM) is an important natural resource. It is fundamental to soil and ecosystem functions across a wide range of scales, from site-specific soil fertility and water holding capacity to global biogeochemical cycling. It is also a highly complex material that is sensitive to direct and indirect human impacts. In SOM research, simulation models play an important role by providing a mathematical framework to integrate, examine, and test the understanding of SOM dynamics. Simulation models of SOM are also increasingly used in more ‘applied’ settings to evaluate human impacts on ecosystem function, and to manage SOM for greenhouse gas mitigation, improved soil health, and sustainable use as a natural resource. Within this context, there is a need to maintain a robust connection between scientific developments in SOM modeling approaches and SOM model applications. This need forms the basis of this review. In this review we first provide an overview of SOM modeling, focusing on SOM theory, data-model integration, and model development as evidenced by a quantitative review of SOM literature. Second, we present the landscape of SOM model applications, focusing on examples in climate change policy. We conclude by discussing five areas of recent developments in SOM modeling including: (1) microbial roles in SOM stabilization; (2) modeling SOM saturation kinetics; (3) temperature controls on decomposition; (4) SOM dynamics in deep soil layers; and (5) SOM representation in earth system models. Our aim is to comprehensively connect SOM model development to its applications, revealing knowledge gaps in need of focused interdisciplinary attention and exposing pitfalls that, if avoided, can lead to best use of SOM models to support policy initiatives and sustainable land management solutions.
Jamin, Timothée; Ruiz-Chavarría, Gerardo; Berhanu, Michael; Falcon, Eric
2014-01-01
We report laboratory experiments on surface waves generated in a uniform fluid layer whose bottom undergoes a sudden upward motion. Simultaneous measurements of the free-surface deformation and the fluid velocity field are focused on the role of the bottom kinematics in wave generation. We observe that the fluid layer transfers bottom motion to the free surface as a temporal high-pass filter coupled with a spatial low-pass filter. Both filter effects are usually neglected in tsunami warning systems. Our results display good agreement with a prevailing linear theory without fitting parameter. Based on our experimental data, we provide a new theoretical approach for the rapid kinematics limit that is applicable even for non-flat bottoms: a key step since most approaches assume a uniform depth. This approach can be easily appended to tsunami simulations under arbitrary topography.
Gravitational-Wave Data Analysis. Formalism and Sample Applications: The Gaussian Case
Piotr Jaranowski
2012-03-01
Full Text Available The article reviews the statistical theory of signal detection in application to analysis of deterministic gravitational-wave signals in the noise of a detector. Statistical foundations for the theory of signal detection and parameter estimation are presented. Several tools needed for both theoretical evaluation of the optimal data analysis methods and for their practical implementation are introduced. They include optimal signal-to-noise ratio, Fisher matrix, false alarm and detection probabilities, ℱ-statistic, template placement, and fitting factor. These tools apply to the case of signals buried in a stationary and Gaussian noise. Algorithms to efficiently implement the optimal data analysis techniques are discussed. Formulas are given for a general gravitational-wave signal that includes as special cases most of the deterministic signals of interest.
Moulin, Emmanuel; Grondel, Sébastien; Assaad, Jamal; Duquenne, Laurent
2008-12-01
The work described in this paper is intended to present a simple and efficient way of modeling a full Lamb wave emission and reception system. The emitter behavior and the Lamb wave generation are predicted using a two-dimensional (2D) hybrid finite element-normal mode expansion model. Then the receiver electrical response is obtained from a finite element computation with prescribed displacements. A numerical correction is applied to the 2D results in order to account for the in-plane radiation divergence caused by the finite length of the emitter. The advantage of this modular approach is that realistic configurations can be simulated without performing cumbersome modeling and time-consuming computations. It also provides insight into the physical interpretation of the results. A good agreement is obtained between predicted and measured signals. The range of application of the method is discussed.
Biswas, Rahul; Cao, Junwei; Essick, Reed; Hodge, Kari Alison; Katsavounidis, Erotokritos; Kim, Kyungmin; Kim, Young-Min; Bigot, Eric-Olivier Le; Lee, Chang-Hwan; Oh, John J; Oh, Sang Hoon; Son, Edwin J; Vaulin, Ruslan; Wang, Xiaoge; Ye, Tao
2013-01-01
The sensitivity of searches for astrophysical transients in data from the LIGO is generally limited by the presence of transient, non-Gaussian noise artifacts, which occur at a high-enough rate such that accidental coincidence across multiple detectors is non-negligible. Furthermore, non-Gaussian noise artifacts typically dominate over the background contributed from stationary noise. These "glitches" can easily be confused for transient gravitational-wave signals, and their robust identification and removal will help any search for astrophysical gravitational-waves. We apply Machine Learning Algorithms (MLAs) to the problem, using data from auxiliary channels within the LIGO detectors that monitor degrees of freedom unaffected by astrophysical signals. The number of auxiliary-channel parameters describing these disturbances may also be extremely large; an area where MLAs are particularly well-suited. We demonstrate the feasibility and applicability of three very different MLAs: Artificial Neural Networks, Su...
Real-Time Leaky Lamb Wave Spectrum Measurement and Its Application to NDE of Composites
Lih, Shyh-Shiuh; Bar-Cohen, Yoseph
1999-01-01
Numerous analytical and theoretical studies of the behavior of leaky Lamb waves (LLW) in composite materials were documented in the literature. One of the key issues that are constraining the application of this method as a practical tool is the amount of data that needs to be acquired and the slow process that is involved with such experiments. Recently, a methodology that allows quasi real-time acquisition of LLW dispersion data was developed. At each angle of incidence the reflection spectrum is available in real time from the experimental setup and it can be used for rapid detection of the defects. This technique can be used to rapidly acquire the various plate wave modes along various angles of incidence for the characterization of the material elastic properties. The experimental method and data acquisition technique will be described in this paper. Experimental data was used to examine a series of flaws including porosity and delaminations and demonstrated the efficiency of the developed technique.
Gravitational-Wave Data Analysis. Formalism and Sample Applications: The Gaussian Case
Królak Andrzej
2005-03-01
Full Text Available The article reviews the statistical theory of signal detection in application to analysis of deterministic gravitational-wave signals in the noise of a detector. Statistical foundations for the theory of signal detection and parameter estimation are presented. Several tools needed for both theoretical evaluation of the optimal data analysis methods and for their practical implementation are introduced. They include optimal signal-to-noise ratio, Fisher matrix, false alarm and detection probabilities, F-statistic, template placement, and fitting factor. These tools apply to the case of signals buried in a stationary and Gaussian noise. Algorithms to efficiently implement the optimal data analysis techniques are discussed. Formulas are given for a general gravitational-wave signal that includes as special cases most of the deterministic signals of interest.
Gravitational-Wave Data Analysis. Formalism and Sample Applications: The Gaussian Case.
Jaranowski, Piotr; Królak, Andrzej
2012-01-01
The article reviews the statistical theory of signal detection in application to analysis of deterministic gravitational-wave signals in the noise of a detector. Statistical foundations for the theory of signal detection and parameter estimation are presented. Several tools needed for both theoretical evaluation of the optimal data analysis methods and for their practical implementation are introduced. They include optimal signal-to-noise ratio, Fisher matrix, false alarm and detection probabilities, [Formula: see text]-statistic, template placement, and fitting factor. These tools apply to the case of signals buried in a stationary and Gaussian noise. Algorithms to efficiently implement the optimal data analysis techniques are discussed. Formulas are given for a general gravitational-wave signal that includes as special cases most of the deterministic signals of interest.
Agresti, Juri; Chen, Yanbei; D'Ambrosio, Erika; Savov, Pavlin
2012-09-01
In this paper, we analytically prove a unique duality relation between the eigenspectra of paraxial optical cavities with nonspherical mirrors: a one-to-one mapping between eigenmodes and eigenvalues of cavities deviating from flat mirrors by h(r) and cavities deviating from concentric mirrors by -h(r), where h need not be a small perturbation. We then illustrate its application to optical cavities, proposed for advanced interferometric gravitational-wave detectors, where the mirrors are designed to support beams with rather flat intensity profiles over the mirror surfaces. This unique mapping might be very useful in future studies of alternative optical designs for advanced gravitational wave interferometers or experiments employing optical cavities with nonstandard mirrors.
Three dimensional full-wave nonlinear acoustic simulations: Applications to ultrasound imaging
Pinton, Gianmarco [Joint Department of Biomedical Engineering, University of North Carolina - North Carolina State University, 348 Taylor Hall, Chapel Hill, NC 27599, USA gfp@unc.edu (United States)
2015-10-28
Characterization of acoustic waves that propagate nonlinearly in an inhomogeneous medium has significant applications to diagnostic and therapeutic ultrasound. The generation of an ultrasound image of human tissue is based on the complex physics of acoustic wave propagation: diffraction, reflection, scattering, frequency dependent attenuation, and nonlinearity. The nonlinearity of wave propagation is used to the advantage of diagnostic scanners that use the harmonic components of the ultrasonic signal to improve the resolution and penetration of clinical scanners. One approach to simulating ultrasound images is to make approximations that can reduce the physics to systems that have a low computational cost. Here a maximalist approach is taken and the full three dimensional wave physics is simulated with finite differences. This paper demonstrates how finite difference simulations for the nonlinear acoustic wave equation can be used to generate physically realistic two and three dimensional ultrasound images anywhere in the body. A specific intercostal liver imaging scenario for two cases: with the ribs in place, and with the ribs removed. This configuration provides an imaging scenario that cannot be performed in vivo but that can test the influence of the ribs on image quality. Several imaging properties are studied, in particular the beamplots, the spatial coherence at the transducer surface, the distributed phase aberration, and the lesion detectability for imaging at the fundamental and harmonic frequencies. The results indicate, counterintuitively, that at the fundamental frequency the beamplot improves due to the apodization effect of the ribs but at the same time there is more degradation from reverberation clutter. At the harmonic frequency there is significantly less improvement in the beamplot and also significantly less degradation from reverberation. It is shown that even though simulating the full propagation physics is computationally challenging it
The development and application of the AstroFit program for complementary dark matter studies
Nguyen, Ngoc-Lan Nelly
2013-02-15
This doctoral thesis describes the development and application of the AstroFit program. Many studies have shown the existence of dark matter (DM), a mass component that constitutes over eighty percent of the entire matter in the Universe. From historical astrophysical evidence to latest reconstructions with sophisticated methods, the gravitational effect of DM can be shown, but its nature remains unknown. Many theoretical explanations aim at describing DM, for example as weakly interacting massive particles (WIMPs), within particular frameworks. The majority of these frameworks extend the existing standard model of particle physics (SM), so that new particles are added to the known set of elementary particles. One of these frameworks is the constrained supersymmetric standard model (CMSSM) that naturally introduces a DM candidate in form of the lightest supersymmetric particle(LSP). Searches for DM particles are undertaken in three different ways. First, directly with fixed-target experiments that measure WIMPs coming towards the Earth with nuclei of the target material. Second, indirectly by reconstructing DM signatures in particle spectra of known particles observed with ground-based telescopes, spaceborne satellites or balloon-borne experiments. And third, indirectly via direct production of DM at particle colliders such as the Large Hadron Collider (LHC) and energy reconstructions where missing transverse energy is presumably carried away by the DM particles. Global fit programs used in particle physics, such as Fittino, are designed to fit parameters of theories beyond the SM simultaneously that are in accordance with the experimental and observed data in order to probe models and constrain the parameter space. To explore complementarity in DM research, the AstroFit interface program has been developed to combine all available information from direct and indirect searches for DM as well as collider searches for new physics in such global fits. To demonstrate
周良明; 郭佩芳; 王强; 杜伊
2004-01-01
Based on the maximum entropy principle, a probability density function (PDF) is derived for the distribution of wave heights in a random wave field, without any more hypothesis. The present PDF, being a non-Rayleigh form, involves two parameters: the average wave height H and the state parameter γ. The role of γ in the distribution of wave heights is examined. It is found that γ may be a certain measure of sea state. A least square method for determining γ from measured data is proposed. In virtue of the method, the values of γ are determined for three sea states from the data measured in the East China Sea. The present PDF is compared with the well known Rayleigh PDF of wave height and it is shown that it much better fits the data than the Rayleigh PDF. It is expected that the present PDF would fit some other wave variables, since its derivation is not restricted only to the wave height.
Young-Ho Park
2006-01-01
Full Text Available This paper presents the methodology for the energy flow analysis of coupled Timoshenko beam structures and various numerical applications to verify the developed methodology. To extend the application of the energy flow model for corrected flexural waves in the Timoshenko beam, which is developed in the other companion paper, to coupled structures, the wave transmission analyses of general coupled Timoshenko beam systems are performed. First, power transmission and reflection coefficients for all kinds of propagating waves in the general, coupled Timoshenko beam structures are derived by the wave transmission approach. In numerical applications, the energy flow solutions using the derived coefficients agree well with the classical solutions for various exciting frequencies, damping loss factors, and coupled Timoshenko beam structures. Additionally, the numerical results for the Timoshenko beam are compared with those for the Euler-Bernoulli beam.
A flexible, wave-shaped P(VDF-TrFE)/metglas piezoelectric composite for wearable applications
You, Sujian; Shi, Huaduo; Wu, Jingen; Shan, Liang; Guo, Shishang; Dong, Shuxiang
2016-12-01
In this work, a wave-shaped piezoelectric composite (WSPC) made of fine β-phase vinylidene fluoride trifluoroethylene copolymer (P(VDF-TrFE)) polymer and high-elastic FeSiB amorphous alloy (metglas) ribbon has been successfully fabricated for wearable device applications. X-ray diffraction and the Fourier Transform Infrared Spectrum studies reveal P(VDF-TrFE) exhibiting the fine β-phase. Both theoretical analysis and experimental results show that unique wave-shaped structure enhances the electromechanical coupling significantly, because of the combination piezoelectric effects of d33 and d31 modes in P(VDF-TrFE) polymer, as well as the enhanced effective piezoelectric coefficient caused by the pre-stretch in P(VDF-TrFE) film. Two application examples of WSPC, (i) mechanical force sensor or energy harvester, and (ii) the medical blood-pressure pulse sensor, have been investigated, which show that the WSPC is a promising candidate for future wearable device applications.
Cai, J; Jiang, D; Wollenweber, Bernd
2012-01-01
The harmonious combination of malting barley yield, quality and nitrogen (N) use-efficiency under nitrogen (N) rates applications was greatly conducive to production in China. The malting barley cultivar Supi 3 was planted during the growing seasons 2005 and 2006 at two contrasting sites in China......, and decreased with 300 kg N ha−1. Net photosynthetic rate (P N) and the amount of accumulated dry matter distributed into grains showed the same response to N application as grain yield. Grain protein content increased with increasing N application rates. Moreover, based on further analysis of these results...
Application of MIMO technology for next-generation optical and millimeter-wave interconnects
Fan, Shu-Hao; Guidotti, Daniel; Chang, Gee-Kung
2012-01-01
Millimeter-wave wireless interconnects is an emerging technology for ultra-short-reach off-chip transmission, providing spatial flexibility and power-efficient high-speed data transportation. Integrated with carrier-over-fiber technology, we propose a low-phase-noise multi-wireless-transceiver architecture to improve the bit-error-rate performance of conventional wireless interconnects. Multiplexing schemes, including frequency division multiplexing, spatial multiplexing, and beam isolation, can be facilitated by carrier-over-fiber techniques. We introduce a potential application of the multi-input-multi-output high-speed analog multiplexing with open-loop analog circuits and digital feedback.
Bandwidth enhancement using Polymeric Grid Array Antenna for millimeter-wave application
Muhamad, Wan Asilah Wan; Ngah, Razali; Jamlos, Mohd Faizal; Soh, Ping Jack; Ali, Mohd Tarmizi
2017-01-01
A new grid array antenna designed on a polymeric polydimethylsiloxane (PDMS) substrate is presented. A good relative permittivity of the PDMS substrate increases the antenna bandwidth. The PDMS surface is also hardened to protect the proposed grid array antenna's radiating element. A SMA coaxial connector is used to feed the 36 × 35 mm2 antenna from its bottom. A bandwidth enhancement of 72.1% is obtained compared to conventional antenna. Besides, its efficiency is increased up to 70%. The simulated and measured results agreed well and the proposed antenna is validated to suit millimeter-wave applications.
Experimental application of ultrasound waves to improved oil recovery during waterflooding
Emad Alhomadhi; Mohammad Amro; Mohammad Almobarky
2014-01-01
In oil reservoirs about 40% of the original oil in place is produced and the rest remains as residual oil after primary and secondary oil recovery due to geological and physical factors. Additional oil can be mobilized by applying some improved oil recovery methods. However, there is no universal IOR method to be implemented in any reservoir. Efforts are made to develop IOR methods with lower risk. One of these methods is the application of sound/ultrasound waves in the reservoirs to overcome...
K2_SPH Method and its Application for 2-D Water Wave Simulation
Zhenhong Hu; Xing Zheng; Wenyang Duan; Qingwei Ma
2011-01-01
Smoothed Particle Hydrodynamics(SPH)is a Lagrangian meshless particle method.However,its low accuracy of kernel approximation when particles are distributed disorderly or located near the boundary is an obstacle standing in the way of its wide application.Adopting the Taylor series expansion method and solving the integral equation matrix,the second order kernel approximation method can be obtained,namely K2_SPH,which is discussed in this paper.This method is similar to the Finite Particle Method.With the improvement of kernel approximation,some numerical techniques should be adopted for different types of boundaries,such as a free surface boundary and solid boundary,which are two key numerical techniques of K2_SPH for water wave simulation.This paper gives some numerical results of two dimensional water wave simulations involving standing wave and sloshing tank problems by using K2_SPH.From the comparison of simulation results,the K2 SPH method is more reliable than standard SPH.
Ivan Aldaya
2015-01-01
Full Text Available Given the interference avoidance capacity, high gain, and dynamical reconfigurability, phased array antennas (PAAs have emerged as a key enabling technology for future broadband mobile applications. This is especially important at millimeter-wave (mm-wave frequencies, where the high power consumption and significant path loss impose serious range constraints. However, at mm-wave frequencies the phase and amplitude control of the feeding currents of the PAA elements is not a trivial issue because electrical beamforming requires bulky devices and exhibits relatively narrow bandwidth. In order to overcome these limitations, different optical beamforming architectures have been presented. In this paper we review the basic principles of phased arrays and identify the main challenges, that is, integration of high-speed photodetectors with antenna elements and the efficient optical control of both amplitude and phase of the feeding current. After presenting the most important solutions found in the literature, we analyze the impact of the different noise sources on the PAA performance, giving some guidelines for the design of optically fed PAAs.
Bliven, L.; Sobieski, P.; Craeye, C.
1998-01-01
Ring waves generated by natural rains from 1 to 100 mm/hr were measured in a small tank located in a field. Time series were obtained: (a) from a wire capacitance probe that measured surface elevation, (b) from an optical gauge that measured rain rates R, (c) from an anemometer that measured wind speeds and (d) from a 13.5 GHz scatterometer (w polarization, and 30 degree incidence angle). Ring wave frequency spectra are computed from the surface elevation data for each minute of rain. All the spectra have a similar shape, with a maximum near 5 Hz, and with a more rapid decay towards higher frequencies than towards lower frequencies. A log-Gaussian spectral model provides a useful representation of these data and analysis of the model coefficients shows that the peak frequency and bandwidth are approximately constant, but the magnitude increases as R increases, Additionally, the normalized radar cross section from the scatterometer varies approximately linearly with the spectral line corresponding to the Bragg-wavelength, so together the log-Gaussian ring wave model and the Bragg scattering theory should be useful for a broad range of applications. These findings can be used to help interpret remote sensing data during rain events and to guide model development for radar scattering from rain roughened seas.
A Love Wave Reflective Delay Line with Polymer Guiding Layer for Wireless Sensor Application
Shitang He
2008-12-01
Full Text Available This paper presents an optimal design for a Love wave reflective delay line on 41o YX LiNbO3 with a polymer guiding layer for wireless sensor applications. A theoretical model was established to describe the Love wave propagation along the larger piezoelectric substrate with polymer waveguide, and the lossy mechanism from the viscoelastic waveguide was discussed, which results in the optimal guiding layer thickness. Coupling of modes (COM was used to determine the optimal design parameters of the reflective delay line structured by single phase unidirectional transducers (SPUDTs and shorted grating reflectors. Using the network analyzer, the fabricated Love wave reflective delay line was characterized, high signal noise ratio (S/N, sharp reflection peaks, and few spurious noise between the peaks were found, and the measured result agrees well with the simulated one. Also, the optimal guiding layer thickness of 1.5~1.8ÃŽÂ¼m was extracted experimentally, and it is consistent with the theoretical analysis.
Szoboszlai, Z; Kertész, Zs; Szikszai, Z; Angyal, A; Furu, E; Török, Zs; Daróczi, L; Kiss, A Z
2012-02-15
In this case study, the elemental composition and mass size distribution of indoor aerosol particles were determined in a working environment where soldering of printed circuit boards (PCB) took place. Single particle analysis using ion and electron microscopy was carried out to obtain more detailed and reliable data about the origin of these particles. As a result, outdoor and indoor aerosol sources such as wave soldering, fluxing processes, workers' activity, mineral dust, biomass burning, fertilizing and other anthropogenic sources could be separated. With the help of scanning electron microscopy, characteristic particle types were identified. On the basis of the mass size distribution data, a stochastic lung deposition model was used to calculate the total and regional deposition efficiencies of the different types of particles within the human respiratory system. The information presented in this study aims to give insights into the detailed characteristics and the health impact of aerosol particles in a working environment where different kinds of soldering activity take place.
Maselli, Andrea; Ferrari, Valeria
2013-01-01
We study how to extract information on the neutron star equation of state from the gravitational wave signal emitted during the coalescence of a binary system composed by two neutron stars or a neutron star and a black hole. We use Post-Newtonian templates which include the tidal deformability parameter and, when tidal disruption occurs before merger, a frequency cut-off. Assuming that this signal is detected by Advanced LIGO/Virgo or ET, we evaluate the uncertainties on these parameters using different data analysis strategies based on the Fisher matrix approach, and on recently obtained analytical fits of the relevant quantities. We find that the tidal deformability is more effective than the stellar compactness to discriminate among different possible equations of state.
Study on the dynamic behavior of matters using laser-driven shock waves in the water confinement
Yu, Hyeonju; Yoh, Jack J.
2015-06-01
The strain rates achievable in laser-driven shock experiments overlap with gas gun and can reach much higher values. The laser-based method also has advantages in terms of system size, cost, repeatability, and controllability. In this research, we aim to measure equation of state, Hugoniot elastic limit, strain rate, and compressive yield strength of target samples by making use of the velocity interferometer or the VISAR. High pressure shock wave is generated by a Q-switched Nd:YAG laser operating at 1.064 μm wavelength with pulse energy up to 3 joules and 9 ns pulse duration. All the experiments are conducted in the water confinement to increase the peak stresses to an order of GPa. Furthermore, quantitative comparisons are made to the existing shock data in order to emphasize the novelty of the proposed setup which is relatively simple and reliable. Corresponding author.
Biswas, Rahul; Blackburn, Lindy; Cao, Junwei; Essick, Reed; Hodge, Kari Alison; Katsavounidis, Erotokritos; Kim, Kyungmin; Kim, Young-Min; Le Bigot, Eric-Olivier; Lee, Chang-Hwan; Oh, John J.; Oh, Sang Hoon; Son, Edwin J.; Tao, Ye; Vaulin, Ruslan; Wang, Xiaoge
2013-09-01
The sensitivity of searches for astrophysical transients in data from the Laser Interferometer Gravitational-wave Observatory (LIGO) is generally limited by the presence of transient, non-Gaussian noise artifacts, which occur at a high enough rate such that accidental coincidence across multiple detectors is non-negligible. These “glitches” can easily be mistaken for transient gravitational-wave signals, and their robust identification and removal will help any search for astrophysical gravitational waves. We apply machine-learning algorithms (MLAs) to the problem, using data from auxiliary channels within the LIGO detectors that monitor degrees of freedom unaffected by astrophysical signals. Noise sources may produce artifacts in these auxiliary channels as well as the gravitational-wave channel. The number of auxiliary-channel parameters describing these disturbances may also be extremely large; high dimensionality is an area where MLAs are particularly well suited. We demonstrate the feasibility and applicability of three different MLAs: artificial neural networks, support vector machines, and random forests. These classifiers identify and remove a substantial fraction of the glitches present in two different data sets: four weeks of LIGO’s fourth science run and one week of LIGO’s sixth science run. We observe that all three algorithms agree on which events are glitches to within 10% for the sixth-science-run data, and support this by showing that the different optimization criteria used by each classifier generate the same decision surface, based on a likelihood-ratio statistic. Furthermore, we find that all classifiers obtain similar performance to the benchmark algorithm, the ordered veto list, which is optimized to detect pairwise correlations between transients in LIGO auxiliary channels and glitches in the gravitational-wave data. This suggests that most of the useful information currently extracted from the auxiliary channels is already described
Swanson, DG
1989-01-01
Plasma Waves discusses the basic development and equations for the many aspects of plasma waves. The book is organized into two major parts, examining both linear and nonlinear plasma waves in the eight chapters it encompasses. After briefly discussing the properties and applications of plasma wave, the book goes on examining the wave types in a cold, magnetized plasma and the general forms of the dispersion relation that characterize the waves and label the various types of solutions. Chapters 3 and 4 analyze the acoustic phenomena through the fluid model of plasma and the kinetic effects. Th
van Driel, Martin; Nissen-Meyer, Tarje; Stähler, Simon; Waszek, Lauren; Hempel, Stefanie; Auer, Ludwig; Deuss, Arwen
2014-05-01
We present a numerical method to compute high-frequency 3D elastic waves in fully anisotropic axisymmetric media. The method is based on a decomposition of the wavefield into a series of uncoupled 2D equations, for which the dependence of the wavefield on the azimuth can be solved analytically. The remaining 2D problems are then solved using a spectral element method (AxiSEM). AxiSEM was recently published open-source (Nissen-Meyer et al. 2014) as a production ready code capable to compute global seismic wave propagation up to frequencies of ~2Hz. It accurately models visco-elastic dissipation and anisotropy (van Driel et al., submitted to GJI) and runs efficiently on HPC resources using up to 10K cores. At very short period, the Fresnel Zone of body waves is narrow and sensitivity is focused around the geometrical ray. In cases where the azimuthal variations of structural heterogeneity exhibit long spatial wavelengths, so called 2.5D simulations (3D wavefields in 2D models) provide a good approximation. In AxiSEM, twodimensional variations in the source-receiver plane are effectively modelled as ringlike structures extending in the out-of-plane direction. In contrast to ray-theory, which is widely used in high-frequency applications, AxiSEM provides complete waveforms, thus giving access to frequency dependency, amplitude variations, and peculiar wave effects such as diffraction and caustics. Here we focus on the practical implications of the inherent axisymmetric geometry and show how the 2.5D-features of our method method can be used to model realistic anisotropic structures, by applying it to problems such as the D" region and the inner core.
Benuzzi, A
1997-12-15
This work is dedicated to shock waves and their applications to the study of the equation of state of compressed matter.This document is divided into 6 chapters: 1) laser-produced plasmas and abrasion processes, 2) shock waves and the equation of state, 3) relative measuring of the equation of state, 4) comparison between direct and indirect drive to compress the target, 5) the measurement of a new parameter: the shock temperature, and 6) control and measurement of the pre-heating phase. In this work we have reached relevant results, we have shown for the first time the possibility of generating shock waves of very high quality in terms of spatial distribution, time dependence and of negligible pre-heating phase with direct laser radiation. We have shown that the shock pressure stays unchanged as time passes for targets whose thickness is over 10 {mu}m. A relative measurement of the equation of state has been performed through the simultaneous measurement of the velocity of shock waves passing through 2 different media. The great efficiency of the direct drive has allowed us to produce pressures up to 40 Mbar. An absolute measurement of the equation of state requires the measurement of 2 parameters, we have then performed the measurement of the colour temperature of an aluminium target submitted to laser shocks. A simple model has been developed to infer the shock temperature from the colour temperature. The last important result is the assessment of the temperature of the pre-heating phase that is necessary to know the media in which the shock wave propagates. The comparison of the measured values of the reflectivity of the back side of the target with the computed values given by an adequate simulation has allowed us to deduce the evolution of the temperature of the pre-heating phase. (A.C.)
Larson, D.B.
1979-01-26
The effects of variation in source and medium properties upon near- and far-field spectra for elastic waves are examined theoretically by considering spherical wave propagation in unbounded elastic media. This type of analysis, although idealized, provides insight into the relative effects of the various source and medium parameters on both tamped and decoupled explosions. It also provides a basis for interpreting both field and laboratory experimental data obtained during spherical wave propagation in real media. In this paper I attempt to unify the work that has been done on spherical wave propagation in elastic media. I present the results in nondimensional forms, in hopes that others may find these forms of the solutions useful and some of the conclusions, based upon my parameter studies, enlightening. Also included is a discussion of some of the limitations of the theory and examples of applications of the spherical wave propagation theory in real media.
Application of ESPRIT in Broad Beam HF Ground Wave Radar Sea Surface Current Mapping
Liu Dan-hong; Wu Xiong-bin; Wen Bi-yang; Cheng Feng
2004-01-01
HF surface wave radar system OSMAR2000 is a broad-beam sea-state detecting radar. ESPRIT (Estimation of Signal Parameters via Rotational Invariance Technique) algorithm is proposed to apply in DOA (direction of arrival) determination of sea echoes. The algorithm of ESPRIT is briefly introduced first. Then discussions are made on the technique for application in the OSMAR2000 framework. Numerical simulation results are presented to demonstrate the feasibility of radial current mapping based on this method. The algorithm manifests significant performance and computational advantages compared with that of MUSIC. Data acquired by OSMAR2000 are processed to give radial current map and the synthesized vector currents are compared with the in-situ measurement with traditional means. The results show the validity of ESPRIT application in DOA determination for broad-beam radar.
Dimova-Malinovska, Doriana; Nesheva, Diana; Pecheva, Emilia; Petrov, Alexander G.; Primatarowa, Marina T.
2012-12-01
We are pleased to introduce the Proceedings of the 17th International School on Condensed Matter Physics: Open Problems in Condensed Matter Physics, Biomedical Physics and their Applications, organized by the Institute of Solid State Physics of the Bulgarian Academy of Sciences. The Chairman of the School was Professor Alexander G Petrov. Like prior events, the School took place in the beautiful Black Sea resort of Saints Constantine and Helena near Varna, going back to the refurbished facilities of the Panorama hotel. Participants from 17 different countries delivered 31 invited lecturers and 78 posters, contributing through three sessions of poster presentations. Papers submitted to the Proceedings were refereed according to the high standards of the Journal of Physics: Conference Series and the accepted papers illustrate the diversity and the high level of the contributions. Not least significant factor for the success of the 17 ISCMP was the social program, both the organized events (Welcome and Farewell Parties) and the variety of pleasant local restaurants and beaches. Visits to the Archaeological Museum (rich in valuable gold treasures of the ancient Thracian culture) and to the famous rock monastery Aladja were organized for the participants from the Varna Municipality. These Proceedings are published for the second time by the Journal of Physics: Conference Series. We are grateful to the Journal's staff for supporting this idea. The Committee decided that the next event will take place again in Saints Constantine and Helena, 1-5 September 2014. It will be entitled: Challenges of the Nanoscale Science: Theory, Materials and Applications. Doriana Dimova-Malinovska, Diana Nesheva, Emilia Pecheva, Alexander G Petrov and Marina T Primatarowa Editors
Faraday Waves-Based Integrated Ultrasonic Micro-Droplet Generator and Applications
Chen S. Tsai
2017-02-01
Full Text Available An in-depth review on a new ultrasonic micro-droplet generator which utilizes megahertz (MHz Faraday waves excited by silicon-based multiple Fourier horn ultrasonic nozzles (MFHUNs and its potential applications is presented. The new droplet generator has demonstrated capability for producing micro droplets of controllable size and size distribution and desirable throughput at very low electrical drive power. For comparison, the serious deficiencies of current commercial droplet generators (nebulizers and the other ultrasonic droplet generators explored in recent years are first discussed. The architecture, working principle, simulation, and design of the multiple Fourier horns (MFH in resonance aimed at the amplified longitudinal vibration amplitude on the end face of nozzle tip, and the fabrication and characterization of the nozzles are then described in detail. Subsequently, a linear theory on the temporal instability of Faraday waves on a liquid layer resting on the planar end face of the MFHUN and the detailed experimental verifications are presented. The linear theory serves to elucidate the dynamics of droplet ejection from the free liquid surface and predict the vibration amplitude onset threshold for droplet ejection and the droplet diameters. A battery-run pocket-size clogging-free integrated micro droplet generator realized using the MFHUN is then described. The subsequent report on the successful nebulization of a variety of commercial pulmonary medicines against common diseases and on the experimental antidote solutions to cyanide poisoning using the new droplet generator serves to support its imminent application to inhalation drug delivery.
Relic gravity waves and 7 keV dark matter from a GeV scale inflaton
F.L. Bezrukov
2014-09-01
Full Text Available We study the mechanism of generation of 7 keV sterile neutrino Dark Matter (DM in the model with light inflaton χ, which serves as a messenger of scale invariance breaking. In this model the inflaton, in addition to providing reheating to the Standard Model (SM particles, decays directly into sterile neutrinos. The latter are responsible for the active neutrino oscillations via seesaw type I mechanism. While the two sterile neutrinos may also produce the lepton asymmetry in the primordial plasma and hence explain the baryon asymmetry of the Universe, the third one being the lightest may be of 7 keV and serve as DM. For this mechanism to work, the mass of the inflaton is bound to be light (0.1–1 GeV and uniquely determines its properties, which allows to test the model. For particle physics experiments these are: inflaton lifetime (10−5–10−12 s, branching ratio of B-meson to kaon and inflaton (10−6–10−4 and inflaton branching ratios into light SM particles like it would be for the SM Higgs boson of the same mass. For cosmological experiments these are: spectral index of scalar perturbations (ns≃0.957–0.967, and amount of tensor perturbations produced at inflation (tensor-to-scalar ratio r≃0.15–0.005.
29th International Symposium on Shock Waves
Ranjan, Devesh
2015-01-01
This proceedings present the results of the 29th International Symposium on Shock Waves (ISSW29) which was held in Madison, Wisconsin, U.S.A., from July 14 to July 19, 2013. It was organized by the Wisconsin Shock Tube Laboratory, which is part of the College of Engineering of the University of Wisconsin-Madison. The ISSW29 focused on the following areas: Blast Waves, Chemically Reactive Flows, Detonation and Combustion, Facilities, Flow Visualization, Hypersonic Flow, Ignition, Impact and Compaction, Industrial Applications, Magnetohydrodynamics, Medical and Biological Applications, Nozzle Flow, Numerical Methods, Plasmas, Propulsion, Richtmyer-Meshkov Instability, Shock-Boundary Layer Interaction, Shock Propagation and Reflection, Shock Vortex Interaction, Shock Waves in Condensed Matter, Shock Waves in Multiphase Flow, as well as Shock Waves in Rarefield Flow. The two Volumes contain the papers presented at the symposium and serve as a reference for the participants of the ISSW 29 and individuals interes...
Wave Separation. Part Two: Applications La séparation des ondes. Deuxième partie : applications
Glangeaud F.
2006-11-01
clearly located it is in the f-k domain, the more efficient the filter is. The method is very cost-effective in CPU time. The KLT or SVD filter requires flattening the wave that is to be extracted, which must additionally be of greater amplitude. Filtering is carried out without any edge effect and the wave amplitude variations are preserved. It serves to separate the normal incidence wave from the other waves and the noise. The SMF filter (spectral matrix is expensive in CPU time It makes the hypothesis that the wave is locally stable and does not require the data to be flattened. It can be used to separate very close neighboring waves without resorting to restrictive a priori hypotheses. It gives a measurement of time delays and also provides a measurement of variations in amplitude and phase spectra during propagation. This measurement is much better than the one supplied by the Wiener method, since it operates on all the traces. Additionally, it is used to separate data into a signal space and a noise space. The parametric method is the most expensive as regards time. It is simple to implement and requires no flattening or preparation of data. It extracts the waves according to chosen parameters, especially time delays. It is particularly recommended in offset vertical seismic profiling where the slowness of upgoing waves is unknown. It is robust with respect to some input parameters if the noise is low in comparison to the signal that is to be extracted. Many applications to field data have illustrated the effectiveness of these wave separation techniques. However, application to a new type of data often requires performance to be monitored to choose the best method. L'identification d'ondes dans les sections utilisées en prospection sismique nécessite parfois de séparer ces ondes. La première partie de cet article a été consacrée au principe et aux méthodes de séparation d'ondes. Les méthodes de séparation d'ondes peuvent être classées en trois familles
Takahashi, Norimasa; Wada, Yuichi; Ohtori, Seiji; Saisu, Takashi; Moriya, Hideshige
2003-09-30
There have been several reports on the use of extracorporeal shock waves in the treatment of pseudarthrosis, calcifying tendinitis, and tendinopathies of the elbow. However, the pathomechanism of pain relief has not been clarified. To investigate the analgesic properties of shock wave application, we analyzed changes in calcitonin gene-related peptide (CGRP)-immunoreactive (ir) dorsal root ganglion (DRG) neurons. In the nontreated group, fluorogold-labeled dorsal root ganglion neurons innervating the most middle foot pad of hind paw were distributed in the L4 and L5 dorsal root ganglia. Of these neurons, 61% were CGRP-ir. However, in the shock wave-treated group, the percentage of FG-labeled CGRP-ir DRG neurons decreased to 18%. These data show that relief of clinical pain after shock wave application may result from reduced CGRP expression in DRG neurons.
Matter-elements model and application for prediction of coal and gas outburst
PENG Shou-jian; XU Jiang; TAO Yun-qi; CHENG Ming-jun
2009-01-01
The theory and method of extenics were applied to establish classical field mat-ter elements and segment field matter elements for coal and gas outburst. A mat-ter-element model for prediction was established based on five matter-elements, which in-cluded gas pressure, types of coal damage, coal rigidity, initial speed of methane diffusion and in-situ stress. Each index weight was given fairly and quickly through the improved analytic hierarchy process, which need not carry on consistency checks, so accuracy of assessment can be improved.
Applications of elastic full waveform inversion to shallow seismic surface waves
Bohlen, Thomas; Forbriger, Thomas; Groos, Lisa; Schäfer, Martin; Metz, Tilman
2015-04-01
Shallow-seismic Rayleigh waves are attractive for geotechnical site investigations. They exhibit a high signal to noise ratio in field data recordings and have a high sensitivity to the S-wave velocity, an important lithological and geotechnical parameter to characterize the very shallow subsurface. Established inversion methods assume (local) 1-D subsurface models, and allow the reconstruction of the S-wave velocity as a function of depth by inverting the dispersion properties of the Rayleigh waves. These classical methods, however, fail if significant lateral variations of medium properties are present. Then the full waveform inversion (FWI) of the elastic wave field seems to be the only solution. Moreover, FWI may have the potential to recover multi-parameter models of seismic wave velocities, attenuation and eventually mass density. Our 2-D elastic FWI is a conjugate-gradient method where the gradient of the misfit function is calculated by the time-domain adjoint method. The viscoelastic forward modelling is performed with a classical staggered-grid 2-D finite-difference forward solver. Viscoelastic damping is implemented in the time-domain by a generalized standard linear solid. We use a multi-scale inversion approach by applying frequency filtering in the inversion. We start with the lowest frequency oft the field data and increase the upper corner frequency sequentially. Our modelling and FWI software is freely available under the terms of GNU GPL on www.opentoast.de. In recent years we studied the applicability of two-dimensional elastic FWI using numerous synthetic reconstruction tests and several field data examples. Important pre-processing steps for the application of 2-D elastic FWI to shallow-seismic field data are the 3D to 2D correction of geometrical spreading and the estimation of a priori Q-values that must be used as a passive medium parameter during the FWI. Furthermore, a source-wavelet correction filter should be applied during the FWI
Ferri, Francesco
untapped, renewable energy resource that has the potential to contribute significantly to the future energy mix, especially in an environmental friendly future scenario. What is bounding the sector to roll off into the market is the cost of the produced energy: too high if compared with other renewable......The idea to use the motion of a wavy sea surface to produce electricity was investigate in the seventies, in a time when the earliest wave energy converters were conceived and developed. But nowadays still none of the patented devices reached a commercial stage. Wave energy is a large, mostly...
Ducharme, R.; da Paz, I. G.
2016-08-01
In two recent papers exact Hermite-Gaussian solutions to relativistic wave equations were obtained for both electromagnetic and particle beams. The solutions for particle beams correspond to those of the Schrödinger equation in the nonrelativistic limit. Here, it will be shown that each beam particle has additional 4-momentum resulting from transverse localization compared to a free particle traveling in the same direction as the beam with the same speed. This will be referred to as the quantum 4-potential term since it will be shown to play an analogous role in relativistic Hamiltonian quantum mechanics as the Bohm potential in the nonrelativistic quantum Hamilton-Jacobi equation. Low-order localization effects include orbital angular momentum, Gouy phase, and beam spreading. Toward a more systematic approach for calculating localization effects at all orders, it will be shown that both the electromagnetic and quantum 4-potentials couple into the canonical 4-momentum of a particle in a similar way. This offers the prospect that traditional methods used to calculate the affect of an electromagnetic field on a particle can now be adapted to take localization effects into account. The prospects for measuring higher order quantum 4-potential related effects experimentally are also discussed alongside some questions to challenge the quantum information and quantum field theorists.
Application of Wavelet Packet De-noising in Time-Frequency Analysis of the Local Wave Method
LI Hong-kun; MA Xiao-jiang; WANG Zhen; ZHU Hong
2003-01-01
The local wave method is a very good time-frequency method for nonstationary vibration signal analysis. But the interfering noise has a big influence on the accuracy of time-frequency analysis. The wavelet packet de-noising method can eliminate the interference of noise and improve the signal-noise-ratio. This paper uses the local wave method to decompose the de-noising signal and perform a time-frequency analysis. We can get better characteristics. Finally, an example of wavelet packet de-noising and a local wave time-frequency spectrum application of diesel engine surface vibration signal is put forward.
Tests and Applications of An Approach to Absorbing Reflected Waves Towards Incident Boundary
张洪生; 王炎; 许春辉; 商辉; 于小伟
2013-01-01
If the upstream boundary conditions are prescribed based on the incident wave only, the time-dependent numerical models cannot effectively simulate the wave field when the physical or spurious reflected waves become significant. This paper describes carefully an approach to specifying the incident wave boundary conditions combined with a set sponge layer to absorb the reflected waves towards the incident boundary. Incorporated into a time-dependent numerical model, whose governing equations are the Boussinesq-type ones, the effectiveness of the approach is studied in detail. The general boundary conditions, describing the down-wave boundary conditions are also generalized to the case of random waves. The numerical model is in detail examined. The test cases include both the normal one-dimensional incident regular or random waves and the two-dimensional oblique incident regular waves. The calculated results show that the present approach is effective on damping the reflected waves towards the incident wave boundary.
Moore, K. D.; Wojcik, M.; Martin, R. S.; Pfeiffer, R.; Prueger, J. H.; Hatfield, J.
2013-12-01
Advancements in elastic light detection and ranging (Lidar) data analysis have made possible the conversion of return signals due to scattering by aerosols to particulate matter (PM) concentrations. This has enabled the use of Lidar systems in PM emissions calculation. Bingham et al. (2009, J. Appl. Rem. Sens., 033510) describes the application of a mass balance technique to estimate emissions from a facility or operation. Additional techniques that utilize the PM calibrated Lidar data are being investigated for use in non-ideal measurement situations, such as limitations on scanning due to physical constraints and obstacles or U.S. Federal Aviation Authority restrictions. The authors are investigating the application of inverse modeling, which uses measured pollutant concentrations resulting from the activity (downwind minus upwind) and an atmospheric dispersion model to calculate the emission rate input into the model that results in the best fit between measured and modeled concentration impacts. Lagrangian stochastic (LS) models, or random flight models, have been shown to simulate atmospheric dispersion and transport fairly well in the surface layer of the atmosphere. A LS model simulates the motion of numerous particles (marked fluid elements or particles) in a fluid based on the fluid's transport and dispersion characteristics plus randomized variations. Several gaseous air pollutant emissions studies have used LS models in inverse modeling in agricultural settings over the past decade. Unlike most gases, particles may have significant settling and deposition due to gravitation forces depending on particle size and density. This may be an important factor, especially in plumes initially dominated by large particles (>~2 μm in diameter), such as in agriculture. Estimates of PM emissions, therefore, should account for particle deposition velocity (vs). In this work we will convert a forward LS model given by Wang et al. (2008, Trans. ASABE, 1763-1774) that
Application of electromagnetic-wave-ionospheric interactions to global warming in the arctic region
Wong, A. Y.
An approach to expel pollutants which can contribute to global warming from the upper atmosphere by the use of HF electromagnetic waves has been proposed [1]. Laboratory plasma experiments have shown that significant gyro-resonance acceleration of minority ion species in a plasma is possible. The separation of ions differing in mass by one unit has been achieved. This method is applicable to the selective acceleration of ions perpendicular to the geomagnetic field in the ionosphere and involves the modulation of the auroral electrojet current to excite ion cyclotron waves. On account of the divergent geomagnetic field in the polar atmosphere the accelerated perpendicular ion velocity is converted into an upward motion along open magnetic field lines. The ions thus removed will not return to the upper atmosphere. Negatively charged particles move upward by the fair-weather electric field and by atmospheric convection. When ions reach above 120˜ km altitude where the ion gyro-frequency is comparable to or greater than the ion-neutral collision frequency, they can be accelerated by electromagnetic fields through the gyro-resonance interaction. By modulating the auroral electrojet in the gyro-frequency range for important minority ion species (˜ 15--30 Hz for CO2-, and Cl-) electromagnetic ion cyclotron waves can be excited, which propagate nearly along the geomagnetic field lines. Experimental evidence for this effect has been obtained with the HIPAS facility [Wong et al., 1997]. When exciting ELF waves over a range of ion gyro-frequencies of dominant ion species, dips were observed in magnetometer data at ion gyro-frequencies of various species, which suggests that the ELF wave energy was absorbed by ions. Similar ion acceleration and expelling phenomenon over the polar regions occurs naturally in so called ion conics as observed by high latitude satellites. Field aligned currents might provide the free energy needed to make this process practical. Field
Li, Bohua; Shapiro, Paul R.; Rindler-Daller, Tanja
2017-06-01
We consider an alternative to WIMP cold dark matter (CDM), ultralight bosonic dark matter (m≥10-22eV) described by a complex scalar field (SFDM) with global U(1) symmetry, for which the comoving particle number density is conserved after particle production during standard reheating. We allow for a repulsive self-interaction. In a ΛSFDM universe, SFDM starts relativistic, evolving from stiff (w=1) to radiationlike (w=1/3), before becoming nonrelativistic at late times (w=0). Thus, before the familiar radiation-dominated era, there is an earlier era of stiff-SFDM-domination, during which the expansion rate is higher than in ΛCDM. SFDM particle mass m and coupling strength λ, of a quartic self-interaction, are therefore constrained by cosmological observables, particularly Neff, the effective number of neutrino species during BBN, and zeq, the redshift of matter-radiation equality. Furthermore, since the stochastic gravitational-wave background (SGWB) from inflation is amplified during the stiff era, it can contribute a radiationlike component large enough to affect these observables by further boosting the expansion rate. Remarkably, this same amplification makes detection of the SGWB possible at high frequencies by current laser interferometer experiments, e.g., aLIGO/Virgo and LISA. For SFDM particle parameters that satisfy these cosmological constraints, the amplified SGWB is detectable by LIGO for a broad range of reheat temperatures Treheat, for values of tensor-to-scalar ratio r currently allowed by CMB polarization measurements. The SGWB is maximally detectable if modes that reentered the horizon when reheating ended have frequencies today in the LIGO sensitive band. For r=0.01, if SFDM parameters are chosen which marginally satisfy the above constraints, the maximally detectable model for (λ/(mc2)2, m)=(10-18eV-1cm3, 8×10-20eV) corresponds to Treheat≈104GeV, for which we predict an aLIGO O1 run detection with SNR~10. Upper limits on the SGWB
Jin, Zhengyu; Gong, Hui; Wang, Kaijun
2015-01-01
The idea of sewage concentration is gradually being accepted as a promising and sustainable way of wastewater resource recovery. In this study, Hybrid coagulation microfiltration (HCM) with air backflushing (AB) was investigated to effectively concentrate organic matter. Compared to direct sewage microfiltration, the addition of coagulation process improved the filtration performance with less fouling trends and better concentration efficiency. The use of AB exhibited even better performance within the same 7-h preliminary concentration period by reducing to one tenth of the resistance and collecting around four times as much organic matter into the product concentrate as in direct sewage microfiltration. During 93-h lab-scale continuous concentration by HCM with AB, a product concentrate with the COD concentration over 15,000 mg/L was achieved and around 70% of total influent organic matter could be recovered. Compared to Direct Membrane Filtration (DMF) with Chemically Enhanced Backwash (CEB), HCM with AB achieved better concentration efficiency with higher concentration extent and concentration velocity along with less organic matter mineralization and the more concentrated product despite with lower organic matter retention. HCM with AB could be a promising effective sewage organic matter concentration for resource recovery under optimization.
First Long-Term Application of Squeezed States of Light in a Gravitational-Wave Observatory
Grote, H; Dooley, K L; Schnabel, R; Slutsky, J; Vahlbruch, H
2013-01-01
In this work we report on the first long-term application of squeezed vacuum states of light to improve the shot-noise-limited sensitivity of a gravitational-wave observatory. In particular, squeezed vacuum was applied to the German/British detector GEO600 during a period of three months from June to August 2011, where GEO600 was performing an observational run together with the French/Italian Virgo detector. Then, after a short interruption, squeezing application continued for about 11 months from November 2011 to October 2012. During this time, squeezed vacuum could be applied for 90.2% (205.2 days total) of the time when science-quality data was acquired with GEO\\,600. The average gain in sensitivity from squeezed vacuum application in this period was 26% (2.0dB), as measured in the frequency band from 3.7 to 4.0kHz, corresponding to a factor of two increase in observed volume of the universe. We show that the glitch-rate of the detector did not increase from squeezing application, confirming the long-term...
Pletikapić, Galja; Ivošević DeNardis, Nadica
2017-01-01
Surface analytical methods are applied to examine the environmental status of seawaters. The present overview emphasizes advantages of combining surface analytical methods, applied to a hazardous situation in the Adriatic Sea, such as monitoring of the first aggregation phases of dissolved organic matter in order to potentially predict the massive mucilage formation and testing of oil spill cleanup. Such an approach, based on fast and direct characterization of organic matter and its high-resolution visualization, sets a continuous-scale description of organic matter from micro- to nanometre scales. Electrochemical method of chronoamperometry at the dropping mercury electrode meets the requirements for monitoring purposes due to the simple and fast analysis of a large number of natural seawater samples enabling simultaneous differentiation of organic constituents. In contrast, atomic force microscopy allows direct visualization of biotic and abiotic particles and provides an insight into structural organization of marine organic matter at micro- and nanometre scales. In the future, merging data at different spatial scales, taking into account experimental input on micrometre scale, observations on metre scale and modelling on kilometre scale, will be important for developing sophisticated technological platforms for knowledge transfer, reports and maps applicable for the marine environmental protection and management of the coastal area, especially for tourism, fishery and cruiser trafficking.
Xiao, Xifeng
One of the main drawbacks that prevent the extensive application of free space laser communications is the atmospheric turbulence through which the beam must propagate. For the past four decades, much attention has been devoted to finding different methods to overcome this difficulty. A partially coherent beam (PCB) has been recognized as an effective approach to improve the performance of an atmospheric link. It has been examined carefully with most analyses considering the Gaussian Schell-model (GSM) beam. However, practical PCBs may not follow GSM theory and are better examined through some numerical simulation approach such as a wave optics simulation. Consequently, an approach for modeling the spatially PCB in wave optics simulation is presented here. The approach involves the application of a sequence of random phase screens to an initial beam field and the summation of the intensity results after propagation. The relationship between the screen parameters and the spatial coherence function for the beam is developed and the approach is verified by comparing results with analytic formulations for a Gaussian Schell-model (GSM) beam. A variety of simulation studies were performed for this dissertation. The propagation through turbulence of a coherent beam and a particular version of a PCB, a pseudo-partially coherent beam (PPCB), is analyzed. The beam is created with a sequence of several Gaussian random phase screens for each atmospheric realization. The average intensity profiles, the scintillation index and aperture averaging factor for a horizontal propagation scenario are examined. Comparisons between these results and their corresponding analytic results for the well-known GSM beam are also made. Cumulative probability density functions for the received irradiance are initially investigated. Following the general simulation investigations, a performance metric is proposed as a general measure for optimizing the transverse coherence length of a partial
Luo, Y.; Xia, J.; Xu, Y.; Zeng, C.; Liu, J.
2010-01-01
Love-wave propagation has been a topic of interest to crustal, earthquake, and engineering seismologists for many years because it is independent of Poisson's ratio and more sensitive to shear (S)-wave velocity changes and layer thickness changes than are Rayleigh waves. It is well known that Love-wave generation requires the existence of a low S-wave velocity layer in a multilayered earth model. In order to study numerically the propagation of Love waves in a layered earth model and dispersion characteristics for near-surface applications, we simulate high-frequency (>5 Hz) Love waves by the staggered-grid finite-difference (FD) method. The air-earth boundary (the shear stress above the free surface) is treated using the stress-imaging technique. We use a two-layer model to demonstrate the accuracy of the staggered-grid modeling scheme. We also simulate four-layer models including a low-velocity layer (LVL) or a high-velocity layer (HVL) to analyze dispersive energy characteristics for near-surface applications. Results demonstrate that: (1) the staggered-grid FD code and stress-imaging technique are suitable for treating the free-surface boundary conditions for Love-wave modeling, (2) Love-wave inversion should be treated with extra care when a LVL exists because of a lack of LVL information in dispersions aggravating uncertainties in the inversion procedure, and (3) energy of high modes in a low-frequency range is very weak, so that it is difficult to estimate the cutoff frequency accurately, and "mode-crossing" occurs between the second higher and third higher modes when a HVL exists. ?? 2010 Birkh??user / Springer Basel AG.
Vera M.F. de Lima
2009-03-01
Full Text Available The isolated chick retina provides an in vitro tissue model, in which two protocols were developed to verify the efficacy of a peptide in the excitability control of the central gray matter. In the first, extra-cellular potassium homeostasis is challenged at long intervals and in the second, a wave is trapped in a ring of tissue causing the system to be under self-sustained challenge. Within the neuropil, the extra-cellular potassium transient observed in the first protocol was affected from the initial rising phase to the final concentration at the end of the five-minute pulse. There was no change in the concomitants of excitation waves elicited by the extra-cellular rise of potassium. However, there was an increase on the elicited waves latency and/or a rise in the threshold potassium concentration for these waves to appear. In the second protocol, the wave concomitants and the propagation velocity were affected by the peptide. The results suggest a synergetic action of the peptide on glial and synaptic membranes: by accelerating the glial Na/KATPase and changing the kinetics of the glial potassium channels, with glia tending to accumulate KCl. At the same time, there is an increase in potassium currents through nerve terminals.Retinas de pinto isoladas proporcionam um modelo de tecidos in vitro, para o qual dois protocolos foram desenvolvidos para verificar a eficácia de um peptídeo no controle da excitabilidade da matéria cinzenta central. No primeiro, a homeostase do potássio extra-celular é desafiada por intervalos longos (1 hora e no segundo, uma onda é capturada em um anel de tecido, de tal maneira que o sistema permaneça em estado de desafio auto-sustentado. Dentro da neuropil, o transiente de potássio extra-celular observado no primeiro protocolo foi afetado da fase de início de aumento à concentração final, ao final do pulso de cinco minutos. Não há mudanças nos parâmetros concomitantes das ondas de excitação geradas
Sarsimbayeva, S. M.; Kospanova, K. K.
2015-11-01
The article provides the discussion of matters associated with the problems of transferring of object-oriented Windows applications from C++ programming language to .Net platform using C# programming language. C++ has always been considered to be the best language for the software development, but the implicit mistakes that come along with the tool may lead to infinite memory leaks and other errors. The platform .Net and the C#, made by Microsoft, are the solutions to the issues mentioned above. The world economy and production are highly demanding applications developed by C++, but the new language with its stability and transferability to .Net will bring many advantages. An example can be presented using the applications that imitate the work of queuing systems. Authors solved the problem of transferring of an application, imitating seaport works, from C++ to the platform .Net using C# in the scope of Visual Studio.
Biswas, Rahul; Blackburn, Lindy L.; Cao, Junwei; Essick, Reed; Hodge, Kari Alison; Katsavounidis, Erotokritos; Kim, Kyungmin; Young-Min, Kim; Le Bigot, Eric-Olivier; Lee, Chang-Hwan;
2014-01-01
The sensitivity of searches for astrophysical transients in data from the Laser Interferometer Gravitationalwave Observatory (LIGO) is generally limited by the presence of transient, non-Gaussian noise artifacts, which occur at a high-enough rate such that accidental coincidence across multiple detectors is non-negligible. Furthermore, non-Gaussian noise artifacts typically dominate over the background contributed from stationary noise. These "glitches" can easily be confused for transient gravitational-wave signals, and their robust identification and removal will help any search for astrophysical gravitational-waves. We apply Machine Learning Algorithms (MLAs) to the problem, using data from auxiliary channels within the LIGO detectors that monitor degrees of freedom unaffected by astrophysical signals. Terrestrial noise sources may manifest characteristic disturbances in these auxiliary channels, inducing non-trivial correlations with glitches in the gravitational-wave data. The number of auxiliary-channel parameters describing these disturbances may also be extremely large; high dimensionality is an area where MLAs are particularly well-suited. We demonstrate the feasibility and applicability of three very different MLAs: Artificial Neural Networks, Support Vector Machines, and Random Forests. These classifiers identify and remove a substantial fraction of the glitches present in two very different data sets: four weeks of LIGO's fourth science run and one week of LIGO's sixth science run. We observe that all three algorithms agree on which events are glitches to within 10% for the sixth science run data, and support this by showing that the different optimization criteria used by each classifier generate the same decision surface, based on a likelihood-ratio statistic. Furthermore, we find that all classifiers obtain similar limiting performance, suggesting that most of the useful information currently contained in the auxiliary channel parameters we extract
Enhanced effects of variation of the fundamental constants in laser interferometers and application to dark matter detection
Stadnik, Y V
2015-01-01
We outline new laser interferometer measurements to search for variation of the electromagnetic fine-structure constant $\\alpha$ and particle masses (including a non-zero photon mass). We propose a strontium optical lattice clock -- silicon single-crystal cavity interferometer as a novel small-scale platform for these new measurements. Multiple passages of a light beam inside an interferometer enhance the effects due to variation of the fundamental constants by the mean number of passages ($N_{\\textrm{eff}} \\sim 10^2$ for a large-scale gravitational-wave detector, such as LIGO, Virgo, GEO600 or TAMA300, while $N_{\\textrm{eff}} \\sim 10^5$ for a strontium clock -- silicon cavity interferometer). Our proposed laser interferometer measurements may be implemented as an extremely precise tool in the direct detection of scalar dark matter that forms an oscillating classical field or topological defects.
The Application of Bayesian Inference to Gravitational Waves from Core-Collapse Supernovae
Gossan, Sarah; Ott, Christian; Kalmus, Peter; Logue, Joshua; Heng, Siong
2013-04-01
The gravitational wave (GW) signature of core-collapse supernovae (CCSNe) encodes important information on the supernova explosion mechanism, the workings of which cannot be explored via observations in the electromagnetic spectrum. Recent research has shown that the CCSNe explosion mechanism can be inferred through the application of Bayesian model selection to gravitational wave signals from supernova explosions powered by the neutrino, magnetorotational and acoustic mechanisms. Extending this work, we apply Principal Component Analysis to the GW spectrograms from CCSNe to take into account also the time-frequency evolution of the emitted signals. We do so in the context of Advanced LIGO, to establish if any improvement on distinguishing between various explosion mechanisms can be obtained. Further to this, we consider a five-detector network of interferometers (comprised of the two Advanced LIGO detectors, Advanced Virgo, LIGO India and KAGRA) and generalize the aforementioned analysis for a source of known position but unknown distance, using realistic, re-colored detector data (as opposed to Gaussian noise), in order to make more reliable statements regarding our ability to distinguish between various explosion mechanisms on the basis of their GW signatures.
Application of Macrofiber Composite for Smart Transducer of Lamb Wave Inspection
Gang Ren
2013-01-01
Full Text Available Macrofiber composite (MFC has been developed recently as a new type of smart material for piezoelectric transducers. It shows advantages over traditional piezoelectric ceramic materials (PZT including the method of application, sensitivity, and cost. It can be embedded on the structure, which provides the possibility to monitor the structural health in real time. In this paper, the feasibility of this transducer for the Lamb wave inspection has been experimentally explored. A pair of MFC patches is bonded on a 2 mm thick aluminum plate, and it has been demonstrated that the dispersive characteristics of S0 and A0 modes, generated and detected by MFC patches, agreed well with the theory. The influence of the bonding condition of the transducer was also tested to show that rigid bonding is required to assure a high amplitude signal. In order to illustrate the performance of defect detection, an artificial defect fabricated on the surface of a specimen was inspected in the pitch-catch mode. The results showed that the MFC transducer is a promising Lamb wave transducer for nondestructive testing (NDT and structural health monitoring (SHM.
High-K ZST material for microwave and millimeter wave applications
Ioachim, A.; Ramer, R.; Toacsan, M. I.; Banciu, M. G.; Nedelcu, L.; Ghetu, D.; Stoica, G.; Annino, G.; Cassettari, M.; Martinelli, M.
2004-02-01
Wireless communications systems require new materials with special properties in specific frequency bands. The investigations on ZST type ceramics, (Zr0.8Sn0.2)TiO4, presented in this paper, recommend this materials for applications in microwaves and millimeter waves. The ZST materials were prepared using a standard solid-state reaction technology. The samples morphology, phase-composition and microstructure investigations were performed by using the scanning electron microscopy (SEM), and energy-disperse X-ray spectrometry (EDX). The crystalline phases were identified by X-ray diffractometry (XRD). The electromagnetic properties were investigated on ZST resonators by using a Computer Aided Measurement (CAM) in microwaves, combining a HP 8757C network analyzer and a HP 8350B sweep oscillator. The dielectric characteristics at millimeter waves were analyzed by investigation of the Whispering Gallery Modes on ZST disks. The low level NiO doping provides ZST materials with temperature coefficient τf in the range (-2 - +4) ppm/°C and decreases the dielectric loss. Materials with high values of the Qf product up to 50,000 and a dielectric constant about 36 at microwave frequencies were obtained. ZST dielectric resonators and substrates for hybrid integrated circuits with dimensions 1" x 1" and thickness in the range 0.6 - 1 mm were manufactured.
SiGe BiCMOS manufacturing platform for mmWave applications
Kar-Roy, Arjun; Howard, David; Preisler, Edward; Racanelli, Marco; Chaudhry, Samir; Blaschke, Volker
2010-10-01
TowerJazz offers high volume manufacturable commercial SiGe BiCMOS technology platforms to address the mmWave market. In this paper, first, the SiGe BiCMOS process technology platforms such as SBC18 and SBC13 are described. These manufacturing platforms integrate 200 GHz fT/fMAX SiGe NPN with deep trench isolation into 0.18μm and 0.13μm node CMOS processes along with high density 5.6fF/μm2 stacked MIM capacitors, high value polysilicon resistors, high-Q metal resistors, lateral PNP transistors, and triple well isolation using deep n-well for mixed-signal integration, and, multiple varactors and compact high-Q inductors for RF needs. Second, design enablement tools that maximize performance and lowers costs and time to market such as scalable PSP and HICUM models, statistical and Xsigma models, reliability modeling tools, process control model tools, inductor toolbox and transmission line models are described. Finally, demonstrations in silicon for mmWave applications in the areas of optical networking, mobile broadband, phased array radar, collision avoidance radar and W-band imaging are listed.
Pisano, Giampaolo; Ade, Peter A R; de Bernardis, Paolo; De Maagt, Peter; Ellison, Brian; Henry, Manju; Ng, Ming Wah; Schortt, Brian; Tucker, Carole
2016-01-01
The quasi-optical modulation of linear polarization at millimeter and sub-millimeter wavelengths can be achieved by using rotating half wave plates (HWPs) in front of polarization sensitive detectors. Large operational bandwidths are required when the same device is meant to work simultaneously across different frequency bands. Previous realizations of half wave plates, ranging from birefringent multi-plate to mesh-based devices, have achieved bandwidths of the order of 100%. Here we present the design and the experimental characterization of a reflective HWP able to work across bandwidths of the order of 150%. The working principle of the novel device is completely different from any previous realization and it is based on the different phase-shift experienced by two orthogonal polarizations respectively reflecting off an electric conductor and off an artificial magnetic conductor.
Pisano, Giampaolo; Maffei, Bruno; Ade, Peter A R; de Bernardis, Paolo; de Maagt, Peter; Ellison, Brian; Henry, Manju; Ng, Ming Wah; Schortt, Brian; Tucker, Carole
2016-12-20
The quasi-optical modulation of linear polarization at millimeter and sub-millimeter wavelengths can be achieved by using rotating half-wave plates (HWPs) in front of polarization-sensitive detectors. Large operational bandwidths are required when the same device is meant to work simultaneously across different frequency bands. Previous realizations of half-wave plates, ranging from birefringent multi-plates to mesh-based devices, have achieved bandwidths of the order of 100%. Here we present the design and experimental characterization of a reflective HWP able to work across bandwidths of the order of 150%. The working principle of the novel device is completely different from any previous realization, and it is based on the different phase-shift experienced by two orthogonal polarizations reflecting, respectively, off an electric conductor and an artificial magnetic conductor.
The visual white matter: The application of diffusion MRI and fiber tractography to vision science
Rokem, Ariel; Takemura, Hiromasa; Bock, Andrew S.; Scherf, K. Suzanne; Behrmann, Marlene; Wandell, Brian A.; Fine, Ione; Bridge, Holly; Pestilli, Franco
2017-01-01
Visual neuroscience has traditionally focused much of its attention on understanding the response properties of single neurons or neuronal ensembles. The visual white matter and the long-range neuronal connections it supports are fundamental in establishing such neuronal response properties and visual function. This review article provides an introduction to measurements and methods to study the human visual white matter using diffusion MRI. These methods allow us to measure the microstructural and macrostructural properties of the white matter in living human individuals; they allow us to trace long-range connections between neurons in different parts of the visual system and to measure the biophysical properties of these connections. We also review a range of findings from recent studies on connections between different visual field maps, the effects of visual impairment on the white matter, and the properties underlying networks that process visual information supporting visual face recognition. Finally, we discuss a few promising directions for future studies. These include new methods for analysis of MRI data, open datasets that are becoming available to study brain connectivity and white matter properties, and open source software for the analysis of these data. PMID:28196374
Wang, Wan-Sheng; Liu, Yuan-Chun; Xiang, Yuan-Yuan; Wang, Qiang-Hua
2016-07-01
We investigate the electronic instabilities in a kagome lattice with Rashba spin-orbital coupling by the unbiased singular-mode functional renormalization group. At the parent 1 /3 filling, the normal state is a quantum spin Hall system. Since the bottom of the conduction band is near the van Hove singularity, the electron-doped system is highly susceptible to competing orders upon electron interactions. The topological nature of the parent system enriches the complexity and novelty of such orders. We find 120∘-type intra-unit-cell antiferromagnetic order, f -wave superconductivity, and chiral p -wave superconductivity with increasing electron doping above the van Hove point. In both types of superconducting phases, there is a mixture of comparable spin singlet and triplet components because of the Rashba coupling. The chiral p -wave superconducting state is characterized by a Chern number Z =1 , supporting a branch of Weyl fermion states on each edge. The model bares close relevance to the so-called s d2 graphenes proposed recently.
INFLUENCE OF LONG TERM APPLICATION OF FERTILIZERS ON SOIL ORGANIC MATTER CONTENT
K.V. Naga Madhuri
2013-06-01
Full Text Available The soil samples were collected from the soils of Long Term Fertilizer Experiments that have been fertilized for the last 25 years from a control plot (receiving no fertilizer/FYM; b plot receiving 100% NPK fertilizer application and c Plot receiving 100% N in the form of FYM, to study the changes in nature and amount of organic matter and these were compared with a similar adjacent soil under natural vegetation. The soil samples were collected from 0-15 cm (surface and 15-30 cm (sub surface layers. The humic substances were fractionated by Tyurins method. The total N and available N content was determined and C/N ratio was calculated. The humic acid was isolated, purified and analyzed for oxygen containing functional groups and spectral properties. It was observed that the soil under natural vegetation had a higher total N while the soil under continuous cultivation had higher available N. The C/N ratio of soil under natural vegetation was high compared to the soil under continuous cultivation. These values were high in surface layers compare to sub surface layers. The oxygen containing functional groups in Humic acid (HA were high in soil under natural vegetation compared to the soil under continuous cultivation. The total acidity and COOH content of surface layers was high compared to sub surface layers in soils under both situations. Phenolic OH groups of subsurface layer was high in soil under natural vegetation and continuous cultivation indicating that this group in sub surface layers and high potential for interaction with clays and metal ions. The higher contents of total acidity and –COOH groups in soil under natural vegetation could be attributed to the difference in chemical composition and molecular weight of humic substances. The E4/E6 ratios of HA’S were less than 5.0 indicating high degree of condensation of aromatic humic acid. The potentiometric titrations of humic acids with standard 0.1 N NaOH indicated a gradual increase
Garcia, Raphael F.; Brissaud, Quentin; Rolland, Lucie; Martin, Roland; Komatitsch, Dimitri; Spiga, Aymeric; Lognonné, Philippe; Banerdt, Bruce
2016-12-01
The propagation of acoustic and gravity waves in planetary atmospheres is strongly dependent on both wind conditions and attenuation properties. This study presents a finite-difference modeling tool tailored for acoustic-gravity wave applications that takes into account the effect of background winds, attenuation phenomena (including relaxation effects specific to carbon dioxide atmospheres) and wave amplification by exponential density decrease with height. The simulation tool is implemented in 2D Cartesian coordinates and first validated by comparison with analytical solutions for benchmark problems. It is then applied to surface explosions simulating meteor impacts on Mars in various Martian atmospheric conditions inferred from global climate models. The acoustic wave travel times are validated by comparison with 2D ray tracing in a windy atmosphere. Our simulations predict that acoustic waves generated by impacts can refract back to the surface on wind ducts at high altitude. In addition, due to the strong nighttime near-surface temperature gradient on Mars, the acoustic waves are trapped in a waveguide close to the surface, which allows a night-side detection of impacts at large distances in Mars plains. Such theoretical predictions are directly applicable to future measurements by the INSIGHT NASA Discovery mission.
P-polarized surface waves in a slab waveguide with left-handed material for sensing applications
Taya, Sofyan A., E-mail: staya@iugaza.edu.ps
2015-03-01
In this paper, surface waves excited at the interface between left-handed and right-handed materials are employed for sensing applications. The propagation of p-polarized (TM) surface waves in a three-layer slab waveguide structure with air core layer as an analyte and anisotropic left-handed materials as claddings is investigated for detection of any changes in the refractive index of the analyte. The dispersion equations and the sensitivity of the effective refractive index to any change in the air layer index are derived, plotted, and discussed in details. The field profile is also explored. It is found that the sensitivity of the proposed surface wave sensor is almost independent of the wavelength of the propagating wave. A considerable sensitivity improvement can be obtained with the increase of transverse components of the left-handed material permittivity. - Highlights: • P-polarized surface waves in a three-layer slab waveguide are employed for sensing applications. • The structure contains air core layer as an analyte and anisotropic left-handed material in the claddings. • The sensitivity is found to be almost independent of the wavelength of the propagating wave. • Unusual sensitivity enhancement is observed as the transverse components of the LHM permittivity increase. • The asymmetric waveguide structure exhibits much higher sensitivity compared to the symmetric one.
Liu, Xu; Greenhalgh, Stewart; Zhou, Bing; Heinson, Graham
2016-12-01
A method using modified attenuation factor function is suggested to determine the parameters of the generalized Zener model approximating the attenuation factor function. This method is applied to constitute the poroviscoelastic model based on the effective Biot theory which considers the attenuative solid frame of reservoir. In the poroviscoelastic model, frequency-dependent bulk modulus and shear modulus of solid frame are represented by generalized Zener models. As an application, the borehole logging dispersion equations from Biot theory are extended to include effects from the intrinsic body attenuation in formation media in full-frequency range. The velocity dispersions of borehole guided waves are calculated to investigate the influence from attenuative bore fluid, attenuative solid frame of the formation and impermeable bore wall.
Bordieu, C.; Rebiere, D.; Pistre, J. [and others
1996-12-31
Pattern recognition techniques based on artificial neural networks are now frequently used with good results for gas sensor signal processing (this includes the detection, the identification and the quantification of gases). In the literature, data sets needed for neural networks are practically always built with steady state sensor responses. This situation prevents these techniques from being used in real time applications. Nevertheless, for example in the case of surface acoustic wave (SAW) gas sensors, because of quite long response times due to kinetic factors concerning the gas adsorption and because gases are sometimes extremely dangerous and/or toxic (NO{sub x}, SO{sub 2}, organophosphorus compounds,...), the detection speed is an essential parameter and hence must be monitored in a real time mode. The purpose of this paper is to propose a new dynamic approach and to illustrate it with SAW sensor responses.
Muhamad, Wan Asilah Wan; Ngah, Razali; Jamlos, Mohd Faizal; Soh, Ping Jack; Ali, Mohd Tarmizi; Narbudowicz, Adam
2017-01-01
This paper introduces a new multilayered polymeric comb array antenna fabricated on a polydimethylsiloxane (PDMS) dielectric substrate. PDMS is selected due to its excellent electrical and mechanical properties such as low permittivity, water resistance and robustness. The polymeric comb array antenna consists of a zigzag array aligned at -90° with respect to the radiating patch with full ground plane. The radiating patch is embedded inside the PDMS substrate while the coaxial connector is located at the bottom of the transmission line. The proposed antenna functions from 22.649 to 27.792 GHz. Simulated and measured reflection coefficients and radiation patterns agreed well. A maximum gain of 9.856 dB is recorded at 25 GHz, indicating suitability for implementation in millimeter-wave applications.
Novel design for microstrip to stripline transitions for millimeter-wave application in LTCC
Xu, Xin; Huang, Qi-bo; Zhu, Zheng-xian; Xu, Hui; Zhang, Bo
2014-11-01
This paper presents two transitions between microstrip and stripline in Low Temperature Co-fired Ceramic technology, including a vertical transition and a coplanar transition for millimeter-wave application. These interconnects are simulated and optimized by a three-dimensional electromagnetic field simulator. Simulation results show that the return loss of microstrip to stripline vertical transition is less than -22 dB, and insertion losses are greater than 0.5 dB up to 35 GHz, and greater than 1 dB up to 40 GHz. Similarly, the return loss of the coplanar transition is less than -32 dB and insertion loss is better than 0.5 dB. LTCC test structures were fabricated and the performance of all transitions was successfully validated by scattering parameter measurements up to 40 GHz.
Xu, Da; Ryan, Kathy L; Rickards, Caroline A; Zhang, Guanqun; Convertino, Victor A; Mukkamala, Ramakrishna
2010-01-01
Pulse wave velocity (PWV) is a marker of arterial stiffness and may permit continuous, non-invasive, and cuff-less monitoring of blood pressure. Here, robust PWV estimation was sought by application of system identification to proximal and distal arterial waveforms. In this approach, the system that optimally couples the proximal waveform to the distal waveform is identified, and the time delay of this system is then used to calculate PWV. To demonstrate proof-of-concept, a standard identification technique was applied to non-invasive impedance cardiography and peripheral arterial blood pressure waveforms from six humans subjected to progressive reductions in central blood volume induced by lower body negative pressure. This technique estimated diastolic pressure with an overall root-mean-squared-error of 5.2 mmHg. For comparison, the conventional detection method for estimating PWV yielded a corresponding error of 8.3 mmHg.
Scalable background-limited polarization-sensitive detectors for mm-wave applications
Rostem, Karwan; Appel, John W; Bennett, Charles L; Chuss, David T; Colazo, Felipe A; Crowe, Erik; Denis, Kevin L; Essinger-Hileman, Tom; Marriage, Tobias A; Moseley, Samuel H; Stevenson, Thomas R; Towner, Deborah W; U-Yen, Kongpop; Wollack, Edward J
2014-01-01
We report on the status and development of polarization-sensitive detectors for millimeter-wave applications. The detectors are fabricated on single-crystal silicon, which functions as a low-loss dielectric substrate for the microwave circuitry as well as the supporting membrane for the Transition-Edge Sensor (TES) bolometers. The orthomode transducer (OMT) is realized as a symmetric structure and on-chip filters are employed to define the detection bandwidth. A hybridized integrated enclosure reduces the high-frequency THz mode set that can couple to the TES bolometers. An implementation of the detector architecture at Q-band achieves 90% efficiency in each polarization. The design is scalable in both frequency coverage, 30-300 GHz, and in number of detectors with uniform characteristics. Hence, the detectors are desirable for ground-based or space-borne instruments that require large arrays of efficient background-limited cryogenic detectors.
Application Aware Topology Generation for Surface Wave Networks-on-Chip
Zhao Fu; Zheng-Bing Hu; Cheng Gong; Wen-Ming Pan; Guo-Bin Lv
2014-01-01
The networks-on-chip (NoC) communica-tion has an increasingly larger impact on the system power consumption and performance. Emerging technologies, like surface wave, are believed to have lower transmission latency and power consumption over the conventional wireless NoC. Therefore, this paper studies how to optimize the network performance and power consumption by giving the packet-switching fabric and traffic pattern of each application. Compared with the conventional method of wire-linked, which adds wireless transceivers by using the genetic algorithm (GA), the proposed maximal declining sorting algorithm (MDSA) can effectively reduce time consumption by as much as 20.4% to 35.6%. We also evaluate the power consumption and configuration time to prove the effective of the proposed algorithm.
Review of radio wave for power transmission in medical applications with safety
Day, John; Geddis, Demetris; Kim, Jaehwan; Choi, Sang H.; Yoon, Hargsoon; Song, Kyo D.
2015-04-01
The integration of biosensors with radio frequency (RF) wireless power transmission devices is becoming popular, but there are challenges for implantable devices in medical applications. Integration and at the same time miniaturization of medical devices in a single embodiment are not trivial. The research reported herein, seeks to review possible effects of RF signals ranging from 900 MHz to 100 GHz on the human tissues and environment. Preliminary evaluation shows that radio waves selected for test have substantial influence on human tissues based on their dielectric properties. In the advancement of RF based biosensors, it is imperative to set up necessary guidelines that specify how to use RF power safely. In this paper, the dielectric properties of various human tissues will be used for estimation of influence within the selected RF frequency ranges.
Research of the applications of ITO in microwave-range surface plasmon waves
Lai, Senfeng; Wu, Wen; Gu, Wenhua
2016-09-01
Because of the electromagnetic field enhancement effect in subwavelength scale, the surface plasmon wave (SPW) has been widely used in beam forming, bio-prospecting, and subwavelength structure design. But most research work is in the visible light or terahertz frequency band, and the surface plasmonic material (SPM) is usually limited to metals. In the microwave band, complex structures have to be used to achieve the desired subwavelength effects, making use of both metal and dielectric materials. In this paper, we propose the excitation of SPW in the microwave range using a simple structure and the material of indium tin oxide (ITO). By measuring the electric field profile during the propagation process, the excitation of SPW in ITO was verified. At the same time, frequency dependence was seen during the propagation process. Therefore, ITO can be a good SPM in the microwave band, just like metals in the visible light band. Considering the transparent characteristics of ITO, it can have many interesting applications.
Transition operators in electromagnetic-wave diffraction theory. II - Applications to optics
Hahne, G. E.
1993-01-01
The theory developed by Hahne (1992) for the diffraction of time-harmonic electromagnetic waves from fixed obstacles is briefly summarized and extended. Applications of the theory are considered which comprise, first, a spherical harmonic expansion of the so-called radiation impedance operator in the theory, for a spherical surface, and second, a reconsideration of familiar short-wavelength approximation from the new standpoint, including a derivation of the so-called physical optics method on the basis of quasi-planar approximation to the radiation impedance operator, augmented by the method of stationary phase. The latter includes a rederivation of the geometrical optics approximation for the complete Green's function for the electromagnetic field in the presence of a smooth- and a convex-surfaced perfectly electrically conductive obstacle.
MM-wave integrated circuits and their applications to communication and automotive systems
Quentin, P.; Dourlens, C.; Camiade, M.; Pons, D.
1999-08-01
After a short presentation of the market outlook of the commercial applications of millimetre-wave systems, we present three examples of a successful development of MMIC chip-sets: one chip-set for a full duplex Ka-band transceiver for a multipoint communication system; one chip-set for a 40 GHz MVDS subscriber terminal and, finally, one chip-set for a 76.5 GHz car radar system for ACC. In all three cases, a full MMIC architecture is used. In our view, this is the only solution to allow the high yield and high volume fabrication of the RF front-end modules at the very low costs which are required for market development.
Scalable Background-Limited Polarization-Sensitive Detectors for mm-wave Applications
Rostem, Karwan; Ali, Aamir; Appel, John W.; Bennett, Charles L.; Chuss, David T.; Colazo, Felipe A.; Crowe, Erik; Denis, Kevin L.; Essinger-Hileman, Tom; Marriage, Tobias A.; Moseley, Samuel H.; Stevenson, Thomas R.; Towner, Deborah W.; U-Yen, Kongpop; Wollack, Edward J.
2014-01-01
We report on the status and development of polarization-sensitive detectors for millimeter-wave applications. The detectors are fabricated on single-crystal silicon, which functions as a low-loss dielectric substrate for the microwave circuitry as well as the supporting membrane for the Transition-Edge Sensor (TES) bolometers. The orthomode transducer (OMT) is realized as a symmetric structure and on-chip filters are employed to define the detection bandwidth. A hybridized integrated enclosure reduces the high-frequency THz mode set that can couple to the TES bolometers. An implementation of the detector architecture at Q-band achieves 90% efficiency in each polarization. The design is scalable in both frequency coverage, 30-300 GHz, and in number of detectors with uniform characteristics. Hence, the detectors are desirable for ground-based or space-borne instruments that require large arrays of efficient background-limited cryogenic detectors.
An FPGA Wave Union TDC for Time-of-Flight Applications
Wu, J.; /Fermilab
2009-01-01
An 18-channel time-of-flight (TOF) grade time-to-digit converter (TDC) has been implemented in a low cost FPGA device. The TDC has the following unique features. (1) The time recording structures of the TDC is based on the 'wave union TDC' we developed in our previous work. A leading edge of the input hit launches a bit pattern, or wave union into the delay chain-register array structure which yields two usable measurements. The two measurements effectively sub-divide timing bins for each other especially the 'ultra-wide bins' caused by the FPGA logic array block (LAB) structure and improves measurement precision both in terms of maximum bin width and RMS resolution. A coarser measurement on input signal trailing edge is also provided for time-over-threshold (TOT) applications. (2) The TDC supports advanced timing reference distribution schemes that are superior to conventional common start/stop schemes. The TDC has 16 regular measurement channels plus two channels for timing reference. The timing reference is established with multiple measurements rather than single shot common start/stop. An advanced scheme, the mean-timing approach even eliminates needs of high quality timing distribution media. (3) The ASIC-like encapsulation of the FPGA TDC significantly shorten the learning curve for potential users while maintain certain flexibility for various applications. Necessary digital post-processing functions including semicontinuous automatic calibration, data buffer, data link jam prevention logic etc. are integrated into the firmware to provide a turn-key solution for users.
Ellipticity and crustal corrections for seismic body wave paths: application to Mars and Moon
Hempel, S.; Garcia, R.; Wieczorek, M. A.
2015-12-01
Forward modeling of seismic body wave travel times and ray parameters for a given density and seismic velocity model is an important tool to investigate the interior structure of planets. The popular toolbox TauP by Crotwell et al. (1999) facilitates application to planets other than Earth, but does not consider a planet's ellipticity nor its surface topography. Due to their ellipticity, smaller radii and larger relative surface topography, these corrections become more significant in predicting seismic observations for celestial bodies like the Moon and Mars. In preparation for NASA's INSIGHT discovery mission (launch in March 2016), we include ellipticity corrections, geometrical spreading and topography corrections into TauP. The respective TauP extensions, as well as Lunar and Martian applications are presented: Previously, Lunar and Martian seismic velocity models have been proposed based on mass, moment of inertia, Love numbers and estimated bulk composition, and in case of the Moon also based on seismic data acquired during the Apollo Program (1969-1977). Due to the lack of direct seismic evidence, current Martian seismic velocity models vary widely and exhibit large travel time excursions, as well as considerable variations in epicentral distance ranges for which a given body wave is predicted to arrive. We discuss the effects of Lunar and Martian ellipticity and crustal structure on seismic travel times for a set of seismic velocity models and compare these to variations observed between the different 1D models. This comparison demonstrates the relevance of modeling the effects of ellipticity and crustal thickness during interpretation of seismic data acquired on planets like Mars or Moon.
Valor, A; Bonche, P
2000-01-01
We present in this paper the general framework of a method which permits to restore the rotational and particle number symmetries of wave functions obtained in Skyrme HF+BCS calculations. This restoration is nothing but a projection of mean-field intrinsic wave functions onto good particle number and good angular momentum. The method allows also to mix projected wave functions. Such a configuration mixing is discussed for sets of HF+BCS intrinsic states generated in constrained calculations with suitable collective variables. This procedure gives collective states which are eigenstates of the particle number and the angular momentum operators and between which transition probabilities are calculated. An application to 24Mg is presented, with mean-field wave functions generated by axial quadrupole constraints. Theoretical spectra and transition probabilities are compared to the experiment.
Arshad, Kashif; Poedts, Stefaan; Lazar, Marian
2017-04-01
Nowadays electromagnetic (EM) fields have various applications in fundamental research, communication, and home appliances. Even though, there are still some subtle features of electromagnetic field known to us a century ago, yet to be utilized. It is because of the technical complexities to sense three dimensional electromagnetic field. An important characteristic of electromagnetic field is its orbital angular momentum (OAM). The angular momentum consists of two distinct parts; intrinsic part associated with the wave polarization or spin, and the extrinsic part associated with the orbital angular momentum (OAM). The orbital angular momentum (OAM) is inherited by helically phased light or helical (twisted) electric field. The investigations of Allen on lasers carrying orbital angular momentum (OAM), has initiated a new scientific and technological advancement in various growing fields, such as microscopy and imaging, atomic and nano-particle manipulation, ultra-fast optical communications, quantum computing, ionospheric radar facility to observe 3D plasma dynamics in ionosphere, photonic crystal fibre, OAM entanglement of two photons, twisted gravitational waves, ultra-intense twisted laser pulses and astrophysics. Recently, the plasma modes are also investigated with orbital angular momentum. The production of electron vortex beams and its applications are indicated by Verbeeck et al. The magnetic tornadoes (rotating magnetic field structures) exhibit three types of morphology i.e., spiral, ring and split. Leyser pumped helical radio beam carrying OAM into the Ionospheric plasma under High Frequency Active Auroral Research Program (HAARP) and characteristic ring shaped morphology is obtained by the optical emission spectrum of pumped plasma turbulence. The scattering phenomenon like (stimulated Raman and Brillouin backscattering) is observed to be responsible for the interaction between electrostatic and electromagnetic waves through orbital angular momentum. The
Lim, C. W.; Zhang, G.; Reddy, J. N.
2015-05-01
approach. Two additional kinds of parameters, the higher-order nonlocal parameters and the nonlocal gradient length coefficients are introduced to account for the size-dependent characteristics of nonlocal gradient materials at nanoscale. To illustrate its application values, the theory is applied for wave propagation in a nonlocal strain gradient system and the new dispersion relations derived are presented through examples for wave propagating in Euler-Bernoulli and Timoshenko nanobeams. The numerical results based on the new nonlocal strain gradient theory reveal some new findings with respect to lattice dynamics and wave propagation experiment that could not be matched by both the classical nonlocal stress model and the contemporary strain gradient theory. Thus, this higher-order nonlocal strain gradient model provides an explanation to some observations in the classical and nonlocal stress theories as well as the strain gradient theory in these aspects.
Active Ionospheric Generation of ELF/VLF Waves.
1985-08-15
extensions. 2. NONLINEAR INTERACTION OF TWO HF WAVE PACKETS WITH AN ELF WAVE IN THE LOWER IONOSPHERE We assume first that the two interactins hish... matter , besides its intrinsic scientific merit, has a broad spectrum of applications, ransins from ionospheric and magnetospheric probing to low...initial wave envelopes are rectansular and the decay waves have small amplitudes; specifically, we let 1a 2 1/1aL=O.O1, la 3 l=O.0. Because we have in mind
Shutova, Yulia; Karna, Barun Lal; Hambly, Adam C.
2016-01-01
Membrane fouling in reverse osmosis (RO) systems caused by organic matter (OM) remains a significant operational issue during desalination. Dissolved air flotation (DAF) has recently received attention as a pre-treatment option for seawater OM removal; however, only a limited number of studies have...
Parnell, John; Lee, Pascal; Osinski, Gordon R.; Cockell, Charles S.
2005-12-01
Organic geochemistry applied to samples of bedrock and surface sediment from the Haughton impact structure detects a range of signatures representing the impact event and the transfer of organic matter from the crater bedrock to its erosion products. The bedrock dolomite contains hydrocarbon-bearing fluid inclusions which were incorporated before the impact event. Comparison of biomarker data from the hydrocarbons in samples inside and outside of the crater show the thermal signature of an impact. The occurrence of hydrocarbon inclusions in hydrothermal mineral samples shows that organic matter was mobilized and migrated in the immediate aftermath of the impact. The hydrocarbon signature was then transferred from bedrock to the crater-fill lacustrine deposits and present-day sediments in the crater, including wind-blown detritus in snow/ice. Separate signatures are detected from modern microbial life in crater rock and sediment samples. Signatures in Haughton crater samples are readily detectable because they include hydrocarbons generated by the burial of organic matter. This type of organic matter is not expected in crater samples on other planets, but the Haughton data show that, using very high resolution detection of organic compounds, any signature of primitive life in the crater rocks could be transferred to surface detritus and so extend the sampling medium.
MEASURING DARK MATTER PROFILES NON-PARAMETRICALLY IN DWARF SPHEROIDALS: AN APPLICATION TO DRACO
Jardel, John R.; Gebhardt, Karl [Department of Astronomy, The University of Texas, 2515 Speedway, Stop C1400, Austin, TX 78712-1205 (United States); Fabricius, Maximilian H.; Williams, Michael J. [Max-Planck Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85741 Garching bei Muenchen (Germany); Drory, Niv, E-mail: jardel@astro.as.utexas.edu [Instituto de Astronomia, Universidad Nacional Autonoma de Mexico, Avenida Universidad 3000, Ciudad Universitaria, C.P. 04510 Mexico D.F. (Mexico)
2013-02-15
We introduce a novel implementation of orbit-based (or Schwarzschild) modeling that allows dark matter density profiles to be calculated non-parametrically in nearby galaxies. Our models require no assumptions to be made about velocity anisotropy or the dark matter profile. The technique can be applied to any dispersion-supported stellar system, and we demonstrate its use by studying the Local Group dwarf spheroidal galaxy (dSph) Draco. We use existing kinematic data at larger radii and also present 12 new radial velocities within the central 13 pc obtained with the VIRUS-W integral field spectrograph on the 2.7 m telescope at McDonald Observatory. Our non-parametric Schwarzschild models find strong evidence that the dark matter profile in Draco is cuspy for 20 {<=} r {<=} 700 pc. The profile for r {>=} 20 pc is well fit by a power law with slope {alpha} = -1.0 {+-} 0.2, consistent with predictions from cold dark matter simulations. Our models confirm that, despite its low baryon content relative to other dSphs, Draco lives in a massive halo.
Overview on the applications of random wave concept in coastal engineering
Goda, Yoshimi
2008-01-01
When “coastal engineering” was recognized as a new discipline in 1950, the significant wave concept was the basic tool in dealing with wave actions on beach and structures. Description of sea waves as the random process with spectral and statistical analysis was gradually introduced in various engineering problems in coastal engineering through the 1970s and 1980s. Nowadays the random wave concept plays the central role in engineering manuals for maritime structure designs. The present paper ...
Caleon, Imelda; Subramaniam, R.
2010-01-01
This study focused on the development and application of a three-tier multiple-choice diagnostic test (or three-tier test) on the nature and propagation of waves. A question in a three-tier test comprises the "content tier", which measures content knowledge; the "reason tier", which measures explanatory knowledge; and the "confidence tier", which…
Gomez, Fabinton Sotelo; Ordóñez, Armando
2016-01-01
Previously a framework for integrating web resources providing educational services in dotLRN was presented. The present paper describes the application of this framework in a rural school in Cauca--Colombia. The case study includes two web resources about the topic of waves (physics) which is oriented in secondary education. Web classes and…
Chukhraiev, N.; Vladimirov, A.; Vilcahuaman, L.; Zukow, W; Samosyuk, N.; Chukhraieva, E.; Butskaya, L.
2016-01-01
SHUPYK NATIONAL MEDICAL ACADEMY OF POSTGRADUATE EDUCATION PONTIFICAL CATHOLIC UNIVERSITY OF PERU RADOM UNIVERSITY SCM «MEDICAL INNOVATIVE TECHNOLOGIES» Chukhraiev N., Vladimirov А., Vilcahuamаn L., Zukow W., Samosyuk N., Chukhraieva E., Butskaya L. COMBINED APPLICATION OF ULTRASONIC WAVES, MAGNETIC FIELDS AND OPTICAL FLOW IN THE REHABILITATION OF P...
Chukhraiev, N.; Vladimirov, A.; Vilcahuaman, L.; Zukow, W.; Samosyuk, N.; Chukhraieva, E.; Butskaya, L.
2016-01-01
SHUPYK NATIONAL MEDICAL ACADEMY OF POSTGRADUATE EDUCATION PONTIFICAL CATHOLIC UNIVERSITY OF PERU RADOM UNIVERSITY SCM «MEDICAL INNOVATIVE TECHNOLOGIES» Chukhraiev N., Vladimirov А., Vilcahuamаn L., Zukow W., Samosyuk N., Chukhraieva E., Butskaya L. COMBINED APPLICATION OF ULTRASONIC WAVES, MAGNETIC FIELDS AND OPTICAL FLOW IN THE REHABILITATION OF P...
Development of GaAs Gunn Diodes and Their Applications to Frequency Modulated Continuous Wave Radar
Choi, Seok-Gyu; Han, Min; Baek, Yong-Hyun; Ko, Dong-Sik; Baek, Tae-Jong; Lee, Sang-Jin; Kim, Jin-Ho; Lee, Seong-Dae; Kim, Mi-Ra; Chae, Yeon-Sik; Kathalingam, Adaikalam; Rhee, Jin-Koo
2010-11-01
In this work, we have designed and fabricated the GaAs Gunn diodes for a 94 GHz waveguide voltage controlled oscillator (VCO) which is one of the important parts in a frequency modulated continuous wave (FMCW) radar application. For fabrication of the high power GaAs Gunn diodes, we adopted a graded gap injector which enhances the output power and conversion efficiency by effectively removing the dead-zone. We have measured RF characteristics of the fabricated GaAs Gunn diodes. The operating current, oscillation frequency, and output power of the fabricated GaAs Gunn diodes are presented as a function of the anode diameters. The operating current increases with anode diameters, whereas the oscillation frequency decreases. The higher oscillation frequency was obtained from 60 µm anode diameters of the fabricated Gunn GaAs diodes and higher power was obtained from 68 µm. Also, for application of the 94 GHz FMCW radar system, we have fabricated the 94 GHz waveguide VCO. From the fabricated GaAs Gunn diodes of anode diameter of 60 µm, we have obtained the improved VCO performance.
Weighted fourier series representation and its application to quantifying the amount of gray matter.
Chung, Moo K; Dalton, Kim M; Shen, Li; Evans, Alan C; Davidson, Richard J
2007-04-01
We present a novel weighted Fourier series (WFS) representation for cortical surfaces. The WFS representation is a data smoothing technique that provides the explicit smooth functional estimation of unknown cortical boundary as a linear combination of basis functions. The basic properties of the representation are investigated in connection with a self-adjoint partial differential equation and the traditional spherical harmonic (SPHARM) representation. To reduce steep computational requirements, a new iterative residual fitting (IRF) algorithm is developed. Its computational and numerical implementation issues are discussed in detail. The computer codes are also available at http://www.stat.wisc.edu/-mchung/softwares/weighted.SPHARM/weighted-SPHARM.html. As an illustration, the WFS is applied i n quantifying the amount ofgray matter in a group of high functioning autistic subjects. Within the WFS framework, cortical thickness and gray matter density are computed and compared.
Yu, Shang-yun; Zhou, Yan-mei
2015-08-01
This paper studied the effects of different concentrations of natural dissolved organic matter (DOM) on the passive sampling technique. The results showed that the presence of DOM affected the organic pollutant adsorption ability of the membrane. For lgK(OW), 3-5, DOM had less impact on the adsorption of organic matter by the membrane; for lgK(OW), > 5.5, DOM significantly increased the adsorption capacity of the membrane. Meanwhile, LDPE passive sampling technique was applied to monitor PAHs and PAEs in pore water of three surface sediments in Taizi River. All of the target pollutants were detected in varying degrees at each sampling point. Finally, the quotient method was used to assess the ecological risks of PAHs and PAEs. The results showed that fluoranthene exceeded the reference value of the aquatic ecosystem, meaning there was a big ecological risk.
Ling, Luo; Fanlong, Meng; Junying, Zhang; Masao, Doi
2016-07-01
When a film of soft matter solutions is being dried, a skin layer often forms at its surface, which is a gel-like elastic phase made of concentrated soft matter solutions. We study the dynamics of this process by using the solute based Lagrangian scheme which was proposed by us recently. In this scheme, the process of the gelation (i.e., the change from sol to gel) can be naturally incorporated in the diffusion equation. Effects of the elasticity of the skin phase, the evaporation rate of the solvents, and the initial concentration of the solutions are discussed. Moreover, the condition for the skin formation is provided. Project supported by the National Natural Science of China (Grant Nos. 21434001, 51561145002, and 11421110001).
Application of Matter Element Analysis Theory for Blasting Classification of Rock
无
2001-01-01
The grading criterion of blasting classification, evaluating index and the characteristic value are taken as matter elements. First, the relational function is constructed according to the grading criterion, and then, the grade of rock blasting is evaluated by the comprehensive relational degree. The author has presented a system method of blasting classification of rock. The practical example proves that it is simple in calculation and reasonable in evaluation.
陈安定; 张文正; 徐永昌
1995-01-01
Isotopic compositions of carbon in the products obtained respectively from 25 sedimentary rocks at an early stage of maturation by the simulated thermogenetic hydrocarbons experiments have been determined. The fractional effect of methane carbon isotope during the thermal maturation of organic matter is observed. Based on the experimental data, the relative equations between δ13C and R0 were established and have been used for differentiation of origins of various kinds of natural gases in the Shan-Gan-Ning Basin.
Sur, S; Sur, Shantanu
2005-01-01
Arterial Blood Pressure wave monitoring is considered to be important in assessment of cardiovascular system. We developed a novel pulse wave detection system using low frequency specific piezoelectric material as pressure wave sensor. The transducer detects the periodic change in the arterial wall diameter produced by pressure wave and the amplified signal after integration represents the pressure wave. The signal before integration is proportional to the rate of change of pressure wave and it not only reproduces the pressure waveform faithfully, but also its sharper nature helps to reliably detect the heart period variability (HPV). We have studied the position-specific (e.g. over carotid or radial artery) nature of change of this pulse wave signal (shape and amplitude) and also the changes at different physiological states.
Directional dark matter by polar angle direct detection and application of columnar recombination
Li, Jin
2015-01-01
We report a systematic study on the directional sensitivity of a direct dark matter detector that detects the polar angle of a recoiling nucleus. A WIMP-mass independent method is used to obtain the sensitivity of a general detector in an isothermal galactic dark matter halo. By using two-dimensional distributions of energy and polar angle, a detector without head-tail information with 6.3 times the statistics is found to achieve the same performance level as a full three-dimensional tracking dark matter detector. Optimum operation orientations are obtained for various experimental configurations, with detectors that are space- or Earth-fixed, have head-tail capability or not, and use energy information or not. Earth-fixed detectors are found to have best sensitivity when the polar axis is oriented at a 45 degree angle from the Earth's pole. The WIMP-mass dependence of the performance of a detector with a 3 keV energy threshold that uses xenon as target material is reported. We apply realistic experimental re...
Application of Matter-element Model in Soil Nutrient Evaluation of Ecological Fragile Region
TANG Jie; WANG Chenye; LIN Nianfeng; LI Zhaoyang; LI Haiyi; MAO Zilong
2009-01-01
On the basis of the soil environment investigation in Da'an City, Jilin Province, China, 40 soil samples from main land use types were obtained and tested by standard method. Soil organic matter (SOM), total N (TN), total P (TP), total K (TK), available N (AN), available P (AP) and available K (AK) were chosen as the evaluation factors. A regional soil nutrient evaluation model was developed based on the matter-element model. The results show that the soil samples with nutrient grade Ⅱ-Ⅴ respectively account for 10%, 30%, 32.5% and 27.5%, and those with grade Ⅳ and Ⅴ account for 60% in all samples. The relationship between soil nutrients and land types indicates that the nutrients of farmland are relatively good, with 41.7% of soil samples with the nutrient grade Ⅳ and Ⅴ. The nutrients of saline-alkali land and sandy land are the worst, with 100% of soil samples with the nutrient grade Ⅳ and Ⅴ. And the ratios of soil samples grade Ⅳ and Ⅴ in grassland and wasteland are respectively 62.5 % and 54.55%. Generally speaking, the soil nutrients status in Da'an City is poor, 60% of soil samples are in poor and extremely poor conditions, indicating that the soil has been severely eroded. Being a relatively superior evaluation method with more accurate resuits and spatial distribution consistency, matter-element analysis is more suitable for regional soil nutrient evaluation than previous models.
An introduction to gauge-gravity duality and its application in condensed matter
Green, A. G.
2013-02-01
The past few years have witnessed a remarkable crossover of string theoretical ideas from the abstract world of geometrical forms to the concrete experimental realm of condensed matter physics. The basis for this - variously known as holography, the AdS/CFT correspondence or gauge-gravity duality - comes from notions right at the cutting edge of string theory. Nevertheless, the insights afforded can often be expressed in ways very familiar to condensed matter physicists. ? The aim of this short, introductory review is to survey the ideas underpinning this crossover, in a way that - as far as possible - strips them of sophisticated mathematical formalism, whilst at the same time retaining their fundamental essence. I will sketch the areas in which progress has been made to date and highlight where the challenges and open questions lie. Finally, I will attempt to give a perspective upon these ideas. What contribution can we realistically expect from this approach and how might it be accommodated into the canon of condensed matter theory? Inevitably, any attempt to do this in such a rapidly evolving field will be superseded by events. Nevertheless, I hope that this will provide a useful way to think about gauge-gravity duality and the uncharted directions in which it might take us.
Zhang, Rui; Zhang, Liangliang; Wu, Tong; Zuo, Shasha; Wang, Ruixue; Zhang, Cunlin; Zhang, Jue; Fang, Jing
2016-04-18
We present a novel contrast-enhanced continuous-terahertz-wave imaging modality based on magnetic induction heating of superparamagnetic iron oxide nanoparticles (SPIOs), which yields a highly sensitive increment in the reflection terahertz (THz) signal in SPIO solution upon exposure to an alternating magnetic field. In the differential and relative refection change focal-plane images before and after alternating magnetic field exposure, a dramatic contrast is demonstrated between water with and without SPIOs. This low-cost, simple, and stable contrast-enhanced continuous-THz-wave imaging system is suitable for miniaturization and real-time imaging application.
Medicus, Heinrich A.
1974-01-01
Discusses the origin of de Broglie's concept and its influences on his contemporaries, notably on Einstein, Schrodinger, Elsasser, Davisson, and Thomson. Indicates that the theory served not only as the starting point of quantum mechanics, but also opened new experimental possibilities. Historical inaccuracies are corrected with new material…
Mortensen, Niels Asger; Pedersen, Jesper
2007-01-01
Optical techniques are finding widespread use in analytical chemistry for chemical and bio-chemical analysis. During the past decade, there has been an increasing emphasis on miniaturization of chemical analysis systems and naturally this has stimulated a large effort in integrating microfluidics and optics in lab-on-a-chip microsystems. This development is partly defining the emerging field of optofluidics. Scaling analysis and experiments have demonstrated the advantage of micro-scale devices over their macroscopic counterparts for a number of chemical applications. However, from an optical point of view, miniaturized devices suffer dramatically from the reduced optical path compared to macroscale experiments, e.g. in a cuvette. Obviously, the reduced optical path complicates the application of optical techniques in lab-on-a-chip systems. In this paper we theoretically discuss how a strongly dispersive photonic crystal environment may be used to enhance the light-matter interactions, thus potentially compen...
Yen, Hung-Ju [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Chemistry Division
2016-11-14
These slides cover Hung-Ju Yen's recent work in the synthesis and structural design of functional materials, which were further used for optoelectronic and energy applications, such as lithium ion battery, solar cell, LED, electrochromic, and fuel cells. This was for a job interview at Center for Condensed Matter Sciences. The following topics are detailed: current challenges for lithium-ion batteries; graphene, graphene oxide and nanographene; nanographenes with various functional groups; fine tune d-spacing through organic synthesis: varying functional group; schematic view of LIBs; nanographenes as LIB anode; rate performance (charging-discharging); electrochromic technology; electrochromic materials; advantages of triphenylamine; requirement of electrochromic materials for practical applications; low driving voltage and long cycle life; increasing the electroactive sites by multi-step synthetic procedures; synthetic route to starburst triarylamine-based polyamide; electrochromism ranging from visible to NIR region; transmissive to black electrochromism; RGB and CMY electrochromism.
Sen, Srimoyee
2016-01-01
We study shock waves in relativistic chiral matter. We argue that the conventional Rankine- Hugoinot relations are modified due to the presence of chiral transport phenomena. We show that the entropy discontinuity in a weak shock wave is linearly proportional to the pressure discontinuity when the effect of chiral transport becomes sufficiently large. We also show that rarefaction shock waves, which do not exist in usual nonchiral fluids, can appear in chiral matter. These features are exemplified by shock propagation in dense neutrino matter in the hydrodynamic regime.
Waves, damped wave and observation
Phung, Kim Dang
2009-01-01
We consider the wave equation in a bounded domain (eventually convex). Two kinds of inequality are described when occurs trapped ray. Applications to control theory are given. First, we link such kind of estimate with the damped wave equation and its decay rate. Next, we describe the design of an approximate control function by an iterative time reversal method.
An application of Love SH waves for the viscosity measurement of triglycerides at high pressures
Rostocki, A. J.; Siegoczyński, R. M.; Kiełczyński, P.; Szalewski, M.
2010-03-01
A new ultrasonic method of viscosity measurements at a high-pressure conditions has been presented. The method is based on the Love wave amplitude measurement. The same electronic setup as in the Bleustein-Gulyaev (B-G) wave method applied by the authors recently for a high-pressure measurement was adopted. The new sensors were made of metallic materials, which make them more reliable at high-pressure conditions. The method has been successfully applied for the viscosity measurement of some triglycerides at high-pressure conditions up to 1 GPa. The results have been compared with the earlier results obtained using B-G waves. This comparison has shown that Love wave method sensors are more reliable than B-G wave sensors and are also cheaper in fabrication, although the sensitivity of Love wave sensors is lower. During the measurement, the phase transitions in the investigated liquids were observed.
Yafeng Xiao
2012-01-01
Full Text Available With the aid of symbolic computation, a new extended Jacobi elliptic function expansion method is presented by means of a new ansatz, in which periodic solutions of nonlinear evolution equations, which can be expressed as a finite Laurent series of some 12 Jacobi elliptic functions, are very effective to uniformly construct more new exact periodic solutions in terms of Jacobi elliptic function solutions of nonlinear partial differential equations. As an application of the method, we choose the generalized shallow water wave (GSWW equation to illustrate the method. As a result, we can successfully obtain more new solutions. Of course, more shock wave solutions or solitary wave solutions can be gotten at their limit condition.
Filippi, P. J. T.
1983-11-01
In has been shown that the sound field reflected by the plane boundary of a layered ground can always be described by a specularly reflected wave, and layer potentials. Despite its generality, this representation is not quite suitable for numerical computation. Dealing with a very simple case, Weyl, and later on Ingard and Thomasson, proposed a representation of the solution in which the layer potential terms are replaced by the sum of surface wave and a Laplace type integral. Such an integral is very convenient for numerical purposes. In this paper, it is shown that this kind of representation can be obtained for a very wide class of sound propagation problems above or within layered media: a half-space bounded by a locally reacting surface, a finite layer of porous medium, a porous medium with depth-varying porosity, a thin elastic plate; wave propagation in shallow water with an impedance bottom. Many other applications could be developed.
Hidden laser communications through matter. An application of meV-scale hidden photons
Jaeckel, Joerg [Durham Univ. (United Kingdom). Inst. for Particle Physics and Phenomenology; Redondo, Javier; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2009-04-15
Currently, there are a number of light-shining-through-walls experiments searching for hidden photons - light, sub-eV-scale, abelian gauge bosons beyond the standard model which mix kinetically with the standard photon. We show that in the case that one of these experiments finds evidence for hidden photons, laser communications through matter, using methods from free-space optics, can be realized in the very near future, with a channel capacity of more than 1 bit per second, for a distance up to the Earth's diameter. (orig.)
Linear power spectra in cold+hot dark matter models analytical approximations and applications
Ma Chung Pei
1996-01-01
This paper presents simple analytic approximations to the linear power spectra, linear growth rates, and rms mass fluctuations for both components in a family of cold+hot dark matter (CDM+HDM) models that are of current cosmological interest. The formulas are valid for a wide range of wavenumber, neutrino fraction, redshift, and Hubble constant: k\\lo 10\\,h Mpc^{-1}, 0.05\\lo \\onu\\lo 0.3, 0\\le z\\lo 15, and 0.5\\lo h \\lo 0.8. A new, redshift-dependent shape parameter \\Gamma_\
Nuclear recoil energy scale in liquid xenon with application to the direct detection of dark matter
Sorensen, P; Dahl, C E
2011-02-14
We show for the first time that the quenching of electronic excitation from nuclear recoils in liquid xenon is well-described by Lindhard theory, if the nuclear recoil energy is reconstructed using the combined (scintillation and ionization) energy scale proposed by Shutt et al.. We argue for the adoption of this perspective in favor of the existing preference for reconstructing nuclear recoil energy solely from primary scintillation. We show that signal partitioning into scintillation and ionization is well-described by the Thomas-Imel box model. We discuss the implications for liquid xenon detectors aimed at the direct detection of dark matter.
A New General Algebraic Method and Its Application to Shallow Long Wave Approximate Equations
无
2007-01-01
A new general algebraic method is presented to uniformly construct a series of exact solutions for nonlinear evolution equations (NLEEs). For illustration, we apply the new method to shallow long wave approximate equations and successfully obtain abundant new exact solutions, which include rational solitary wave solutions and rational triangular periodic wave solutions. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in mathematical physics.
Cavity-Backed Angled-Dipole Antennas for Millimeter-Wave Wireless Applications
Son Xuat Ta
2016-01-01
Full Text Available A cavity-backed angled-dipole antenna is proposed for millimeter-wave wireless applications. The angled-dipole radiator is built on both sides of an RT/Duroid 5880 substrate (εr=2.2 and fed by a parallel-plate transmission line. The cavity-backed reflector is utilized to improve the radiation characteristics of the angled dipole, such as gain, back-radiation, symmetric pattern, and similar 3 dB beamwidth in the E- and H-planes. The design, with a cavity aperture of 0.5λ28-GHz×0.5λ28-GHz, results in a S11<-10 dB bandwidth of 26.7–30.6 GHz, a gain of 6.6–8.0 dB, and a similar 3 dB beamwidth of approximately 70° for both the E- and H-planes. Eight-element linear arrays with the proposed antenna having a center-to-center spacing of 5.6 mm (0.52λ28-GHz are characterized, fabricated, and measured. By applying nonuniform power distribution across excitations, the array achieves a scan angle up to 40° and a sidelobe level below −15 dB.
Park, Jae-Hyoung; Baek, Chang-Wook; Jung, Sanghwa; Kim, Hong-Teuk; Kwon, Youngwoo; Kim, Yong-Kweon
2000-12-01
In this paper, novel micromachined coplanar waveguide(CPW) transmission lines for application in millimeter-wave circuits are proposed. Two types of transmission lines with the length of 1 cm are fabricated and the measured characteristics are compared with those of the conventional CPW transmission line. One is the elevated CPW(ECPW) transmission line and the other is the overlay CPW(OCPW) line. These transmission lines are composed of 3-μm-thick electroplated gold lines with overhanging parts. By elevating the metal lines from the substrate using micromachining technology, the conductor and substrate dielectric loss can be reduced and easily integrated with conventional monolithic microwave integrated circuits. Compared with the conventional CPW line showing 2.65 dB/cm insertion loss at 50 GHz, the loss can be reduced to 1.9 dB/cm and 1.25 dB/cm at 50 GHz in the case of the ECPW and OCPW transmission lines, respectively. Also, the OCPW transmission line shows that the insertion loss does not vary with the change of the characteristic impedance. As shown in the measured and simulated results, the insertion loss is maintained below 1.4 dB/cm over wide impedance ranges.
Commercialization of an S-band standing-wave electron accelerator for industrial applications
Moon, Jin-Hyeok; Kwak, Gyeong-Il; Han, Jae-Ik; Lee, Gyu-Baek; Jeon, Seong-Hwan; Kim, Jae-Young; Hwang, Cheol-Bin; Lee, Gi-Yong; Kim, Young-Man; Park, Sung-Ju
2016-09-01
An electron accelerator system has been developed for use in industrial, as well as possible medical, applications. Based on our experiences achieved during prototype system development and various electron beam acceleration tests, we have built a stable and compact system for sales purposes. We have integrated a self-developed accelerating cavity, an E-gun pulse driver, a radio-frequency (RF) power system, a vacuum system, a cooling system, etc. into a frame with a size of 1800 × 1000 × 1500 mm3. The accelerating structure is a side-coupled standing-wave type operating in the π/2 mode (tuned to~3 GHz). The RF power is provided by using a magnetron driven by a solid-state modulator. The electron gun is a triode type with a dispenser cathode (diameter of 11 mm). The system is capable of delivering a maximum 900-W average electron beam power with tight focusing at the target. Until now, we have performed various electron beam tests and X-ray beam tests after having built the system, have completed the beam assessment for commercializations, and have been preparing full-fledged sales activity. This article reports on our system development processes and on some of our early test results for commercializations.
Compressive sensing of full wave field data for structural health monitoring applications
di Ianni, Tommaso; De Marchi, Luca; Perelli, Alessandro
2015-01-01
Numerous nondestructive evaluations and structural health monitoring approaches based on guide waves rely on analysis of wave fields recorded through scanning laser Doppler vibrometers (SLDVs) or ultrasonic scanners. The informative content which can be extracted from these inspections is relevant...... performance is mostly influenced by the choice of a proper decomposition basis to exploit the sparsity of the acquired signal. Here, different bases have been tested to recover the guided waves wave field acquired on both an aluminum and a composite plate. Experimental results show that the proposed approach...
Wave induced mixing and transport of buoyant particles: application to the Statfjord A oil spill
M. Drivdal
2014-05-01
Full Text Available The modelling of wave-current and wave-turbulence interactions have received much attention in recent years. In this study the focus is on how these wave effects modify the transport of particles in the ocean. Here the particles are buoyant tracers that can represent oil droplets, plastic particles or plankton, for example fish eggs and larvae. Using the General Ocean Turbulence Model (GOTM, modified to take surface wave effects into account, we investigate how the increased mixing by wave breaking and Stokes shear production as well as the stronger veering by the Coriolis–Stokes force affect the drift of the particles. The energy and momentum fluxes as well as the Stokes drift depend on the directional wave spectrum that can be obtained from a wave model or from observations. As a first test the depth and velocity scales from the model are compared with analytical solutions based on a constant eddy viscosity (e.g. classical Ekman theory. Secondly the model is applied to a case where we investigate the oil drift after an offshore oil spill outside the western coast of Norway in 2007. During this accident the average net drift of oil was observed to be both slower and more deflected away from the wind direction than predicted by empirical models. With wind and wave forcing from the ERA Interim archive, it is shown that the wave effects are important for the resultant drift in this case, and has the potential to improve drift forecasting.